Category Archives: Health Policy

When Reasonable Policy Discussions Become Unreasonable Personal Attacks

Recently I was reminded of the controversy that erupted late in 2014 about remarks made by the distinguished health economist, Jonathan Gruber, professor at MIT for two decades. Professor Gruber, one of the country’s leading experts on health policy, had played an important role in the construction of the Obama administration’s Patient Protection and Affordable Care Act, subsequently derided by its political opponents as “Obamacare.”

A brief but intense political controversy and media feeding-frenzy erupted when videos surfaced in which Professor Gruber – largely in a series of academic seminars and conferences – explained how the Act was crafted and marketed in ways that would make it easier to develop political support. For example, he noted that insurance companies were taxed instead of patients, fundamentally the same thing economically, but vastly more palatable politically. He went on to note that this was possible because of “the lack of economic understanding of the American voter.” His key point was that the program’s “lack of transparency is a huge political advantage.” Is that a controversial or even unique observation?

A Truism of Political Economy

Any economist who has worked on the development or analysis of public policy – in areas ranging from health care policy to environmental policy to financial regulation – recognizes the truth of the key insight Gruber was communicating to his audiences. It is inevitably in the interests of the advocates of a policy to make the policy’s benefits transparent and to make its costs vague, even unobservable; just as it is in the interests of the opponents of a policy to make that policy’s benefits obscure and its costs as clear as the light of day.

The specific construction of hundreds of public policies are explained by this truism. In the United States, Corporate Average Fuel Economy Standards (or “CAFE standards”) have been a bipartisan Congressional success, despite the fact that the costs they place on the American public per unit of fuel savings are vastly greater than the costs of a commensurate increase in gasoline taxes. Likewise, when conservative opponents of CO2 cap-and-trade wanted to stop the House-passed bill in its tracks, they resorted to demonizing it as “cap-and-tax.”

So, the central lesson Professor Gruber was offering is hardly controversial, and its enunciation ought not lead to the terrible attacks that he suffered. He doesn’t need me to defend him, but he was unfairly demonized, simply because people disagreed with him politically regarding the merits of the public policy he had helped develop and support.

Unfortunately, I was reminded of this recently when I found myself subject to attempted demonization, because someone did not agree with a policy I supported. What happened to me is trivial compared with what Professor Gruber has gone through, but it prompts me to write about it today.

Can We Agree to Disagree?

I have written before at this blog about the reasons why I support my university’s decision not to divest its endowment of its fossil-fuel company holdings. I won’t repeat those arguments here, but will note that I have gone out of my way not to draw conclusions or make recommendations about what other universities or other institutions ought to do in this regard, including when I agreed to write an essay on the subject for Yale Environment 360. My analysis and conclusions were not developed in spite of my decades of research, teaching, and outreach on global climate change policy; rather, they were developed because of my years of work in this area.

There are people, some of whom I greatly respect, who have different perspectives on this issue, and have come to very different conclusions than have I. We have essentially agreed to disagree. They haven’t cast aspersions on me, nor I on them. As my writings on this topic have illustrated, there are many facets to the issue, including economics, politics, ethics, and even religion. No one has cornered the market on wisdom.

And What About the Keystone XL Pipeline?

Likewise, on a quite different topic, on January 8, 2015, Coral Davenport wrote a story in the New York Times about the political debates in Washington regarding the proposed Keystone XL pipeline, and stated that “… most energy and policy experts say the battle over Keystone overshadows the importance of the project as an environmental threat or an engine of the economy. The pipeline will have little effect, they say, on climate change, production of the Canadian oil sands, gasoline prices and the overall job market in the United States.” She went on to quote me (accurately) as having said, “The political fight about Keystone is vastly greater than the economic, environmental or energy impact of the pipeline itself. It doesn’t make a big difference in energy prices, employment or climate change either way.” What I said was consistent with the evidence at the time (note, however, that as oil prices fall, the possibility increases that the Canadian oil sands would be uneconomic to develop without the pipeline). Once again, the analysis is not one-dimensional, and reasonable people can respectfully disagree.

When Policy Debates Become Personal Attacks

But these two topics – the Keystone XL pipeline and fossil-fuel divestment – have increasingly become engulfed in highly-charged campaigns and exceptionally heated political debates. As part of this, my integrity was recently attacked, because of my views.  A young and – I’m sure – well-intentioned climate activist and journalist, writing in the Huffington Post, implied that my assessment in the New York Times of the Washington political debates regarding Keystone XL and my support for Harvard’s divestment policy, are because “Stavins has done consulting work for Chevron, Exelon, Duke Energy and the Western States Petroleum Association.”

The author of the Huffington Post piece selected those three companies and one trade association from a list of 92 “Outside Activities” that I voluntarily provide as a means of public disclosure. The author chose not to note that the vast majority of my outside engagements are with universities, think tanks, environmental advocacy NGOs, foundations, the U.S. Environmental Protection Agency, other federal agencies and departments, international organizations, and environment ministries around the world (not to mention a set of Major League Baseball teams, but that’s another story altogether).

But what about the four he did choose to highlight? First, I am very proud of my work supported by Chevron and the closely-related Western States Petroleum Association, in which I have carried out a series of analyses studying how to strengthen and improve California’s climate policy under AB-32. That’s right – developing and assessing ways to make the AB-32 cap-and-trade system and the related suite of “complementary policies” more environmentally effective, more cost-effective, and more equitable (I’ve written about this work several times at this blog).

Likewise, my work supported by Duke Energy began a decade ago when I helped the former CEO bring home to his senior management the importance of climate change and the importance of well-designed public policies (in particular, carbon cap-and-trade) to address it. All of my subsequent work supported by Duke Energy likewise has focused on the design of better market-based instruments – cap-and-trade – to reduce CO2 emissions.

And, finally, what about Exelon? This was interesting and important work I carried out with my friend and colleague, MIT Professor Richard Schmalensee, Dean Emeritus of the Sloan School of Management (I wrote about this work at this blog and at the Huffington Post). In 2011, with support from Exelon, Professor Schmalensee and I analyzed EPA’s proposals for new rules to regulate the interstate transport of sulfur dioxide and nitrogen oxides emitted from electric power generation facilities. You can read in detail about our multi-faceted assessment, but the bottom-line is that we provided strong support for a stringent rule. Our brief summary at the University of Pennsylvania’s RegBlog concludes: “In sum, while imposing incremental costs to achieve reductions in SO2 and NOX emissions, the Transport Rule would produce significant benefits in terms of improved health outcomes, and better environmental amenities and services, which studies estimate significantly outweigh the costs.”

Sadness and Empathy

It is nothing less than absurd – and, frankly, quite sad – that someone would suggest that my views on divestment and my New York Times quote on the politics of Keystone XL were somehow due to my having received previous support for analytical work for an oil company, a trade association, and two electric utilities. This was an unfortunate move to question my credibility and damage my reputation in a misguided attempt to demonize me, rather than engage in reasonable discussion and debate. Unfortunately, most of those who have read the activist/journalist’s original commentary and have possibly repeated his claims to others will not see the essay you have just read.

This is surely nothing compared with what Professor Gruber has gone through, but it has certainly increased my empathy for him, as well as my admiration.


Personal Attacks: An Even Sadder Epilogue

It’s nearly two months since I wrote the essay above, but a series of recent events prompts me to add this sad epilogue.  My family and I have recently been subject to cyber-bullying, harassment, and threats, because of my public stance in support of Harvard’s decision not to divest from its endowment portfolio its holdings of fossil-fuel company stocks.

In particular, the most recent message sent to me said in part: “You may be assured that I will have a lot to say about your vocal public support of Harvard’s fossil fuel investments, … and that I have a particular interest in making sure that [your] financial connections to the fossil fuel industry are made fully public …” This threat to tarnish my reputation by publicizing a supposed conflict of interest is striking for a number of reasons:

  • In several essays at this blog and elsewhere, I have carefully explained my reasons for supporting Harvard’s decision not to divest;
  • In several essays at this blog and elsewhere, I have been completely up front about receiving support for (publically available) analytical work I’ve carried out for private-sector companies (and have long provided a list of all outside engagements at my website);
  • In the essay above, I documented the fundamentally pro-environment, policy-analytic work I had done for the specific companies mentioned; and
  • The claim that my position regarding Harvard divestment has somehow been influenced by my work with an oil company and an industry trade association defies logic.

The last item on this list – the fundamental illogic of such a claim – merits explanation. People on all sides of the divestment issue (including leaders of the student movement, and including the person who wrote the threat I quoted above) acknowledge that divestment will have no direct financial impacts on the respective companies. Rather, the merit of divestment that is most frequently cited by supporters is its symbolic value. Because divestment has no financial impacts on the fossil-fuel companies, those companies don’t care much about it. They would not care one way or the other what I might have to say on the topic. Hence, even if I did want to curry favor with those companies, that would not lead me (or anyone else) to take a particular position on the divestment issue.

The more important question to ask is whether my research, teaching, and outreach initiatives on climate change economics and policy have been biased by my having carried out consulting assignments for an oil company and trade association (two of a hundred outside engagements over the past several years)? That is, if there really was a conflict of interest, then in an effort to make those companies happy, I would presumably pull my punches regarding recommendations of what does matter to those companies – public policies that will reduce their profits by increasing their costs of doing business and/or by reducing demand for their products. But nothing could be further from the truth!

For a decade or more, my research, teaching, and outreach have focused on more enlightened, stronger, and better climate change policies. I have been outspoken in regard to the pressing need for well-designed carbon-price instruments at the national and sub-national levels, and for the need for better, more effective international climate policies, both under the United Nations Framework Convention on Climate Change and through other venues. This is reflected in my published research, my teaching, and my outreach efforts, including through this blog.

It is ironic, offensive, and sad that anyone would suggest that my support of Harvard’s divestment position is somehow tied to my outside engagements. That suggestion – and the recent threats I have received – defies logic and is contradicted by the record.

On the Origins of Research

In response to my last essay at this web site, “On Becoming an Environmental Economist,” several readers suggested that someday I should write about the origins of my various research initiatives over the past 25 years.  Today, I’m doing that sooner than anyone might have expected!

This is feasible because — also quite recently — I was asked by my colleague, Hannah Riley Bowles, the instructor in the Harvard Kennedy School’s Doctoral Research Seminar, to make a presentation to the first-year students in the Ph.D. program in public policy on how research programs develop.  To prepare for this, I reflected on my research projects over the past 25 years since receiving my PhD in economics at Harvard and joining the Kennedy School faculty, and as I began to write some notes for my presentation, a flow chart of research origins, subjects, and products started to emerge.  You can view my PowerPoint presentation (you need to use Slide Show mode to see the animation) here.

In this essay, I describe the elements of that flow chart of research sources, topics, and selected publications (and provide some screen shots of the PowerPoint deck).

As will probably be apparent, I found the process of preparing for Professor Bowles’s seminar valuable, because it forced me – for the first time in 25 years – to step back and reflect systematically on the origins of my research projects and the connections among them.  So, I recommend this process to other researchers, as I think you may find it rewarding.  And, for would-be researchers, that is, PhD students, I hope the results below will be informative.

An Ex Post Exploration of How Research Programs Develop

In carrying out this ex post exploration of how research programs may develop, I identified eleven types of sources of research ideas and projects.  In approximate chronological order (but not necessarily in order of importance), these are:

      • Dissertation
      • Involvement with the Policy World
      • Picking Up on Someone Else’s Work
      • Conferences
      • Funders
      • Student Interest
      • Responding to Others’ Work
      • Teaching
      • Consulting
      • Class Assignment
      • Invitation

I begin with how my dissertation research subsequently led to several avenues of further research and writing.

Dissertation — Analyzing Land Use

My 1988 Ph.D. thesis examined econometrically the factors that had led to the dramatic depletion of forested wetlands in the southern United States over the previous five decades.  Before commenting on how my dissertation stimulated my subsequent research, I should acknowledge that my dissertation topic itself grew of out of some consulting work I was doing at the time for the Environmental Defense Fund, in particular an analysis for James T. B. Tripp of how U.S. Army Corps of Engineers flood control projects were providing economic incentives for landowners to convert their forested wetlands to agricultural croplands.

My dissertation led directly to a pair of journal articles published in 1990 in the American Economic Review (with Adam Jaffe) and the Journal of Environmental Economics and Management.  But more striking – given the theme of this essay – is that several years later I realized that the general econometric approach and simulation model could be applied to a very different question, namely, analyzing the anticipated costs of biological carbon sequestration as a means of reducing net concentrations of carbon dioxide (CO2) in the atmosphere, linked with global climate change.  That recognition led to another article in the American Economic Review (1999), and then to a series of other, related projects on carbon sequestration (with Richard Newell 2000, and with Ruben Lubowski and Andrew Plantinga 2006, both in the Journal of Environmental Economics and Management), as well as a broader research initiative on factors affecting land-use decisions (with Plantinga and Lubowski in the Journal of Urban Economics in 2002 and Land Economics in 2008).  More recent work with Andrew Plantinga and Robin Cross (that does not appear in the schematic below) has involved an econometric analysis of the concept and reality of “terroir” associated with the production of premium wines (American Economic Review 2011, Journal of Wine Economics 2011).

A Less Direct Legacy of Dissertation:  Economics of Technological Change

A fundamental aspect of the econometric modeling involved in some of the land-use models above, including my dissertation research, was the estimation of the parameters of an empirical distribution of some heterogeneous attribute of land parcels, such as potential crop revenue (due to varying land quality, for example).  As costs of production fall, for example, that distribution would be swept, with various parcels going into production at various points in time.  Adam Jaffe and I hoped that this same sort of model could be applied to the process of technological diffusion, that is, the process of gradual adoption of some new technology over time.

As it turned out, however, the model was less useful than we first thought it would be for analyzing the factors affecting technology diffusion, and so we abandoned it for that purpose.  But this led us to explore other conceptual and empirical approaches to assessing the factors that lead to the diffusion of environmental technologies.  We developed a new framework for comparing empirically the effects of alternative environmental policy instruments on the diffusion of new technology, including Pigouvian taxes, technology adoption subsidies, and technology standards, with an empirical application to the diffusion of thermal insulation in new home construction, comparing the effects of energy prices, insulation cost, and building codes (Journal of Environmental Economics and Management 1995).  Related work with Nolan Miller and Lori (Snyder) Bennear followed in 2003 (American Economic Review).

Given our interest in the diffusion (adoption) of energy-efficiency technologies, it was natural to think about exploring the factors that affect the innovation (commercialization) of such technologies.  A very different model was developed — with Richard Newell taking the lead as part of his Harvard dissertation research — and an empirical application was made to analyzing the innovation of specific household energy-consuming durable goods (such as water heaters and air conditioners).  This work appeared in the Quarterly Journal of Economics in 1999.

More broadly, our interest in the innovation and diffusion energy efficiency technologies led us to explore in a series of articles the so-called “energy paradox” of apparently slow diffusion of technologies that appear to pay for themselves, as well as other issues related to energy-efficiency technological change (Energy Journal 1994, Resource and Energy Economics 1994, Energy Policy 1994, Elsevier Handbook of Economics 2003, Ecological Economics 2005, Energy Economics 2006, and many others).  And, recently, with a resurgence of interest in the energy paradox in the context of global climate change, Richard Newell and I have launched a new research initiative, with support from the Alfred P. Sloan Foundation.

Because I’ve sought to describe the origins of my research somewhat chronologically, I began with my dissertation research.  The fact that several strands of research — some directly related and some indirectly related to my dissertation — subsequently emerged will surely not surprise academic readers of this essay.  However, a considerably greater influence (indeed, the most important influence) on my research portfolio has come from my involvement — not with fellow scholars — but with practitioners in the world of public policy.  That may come as a surprise to some readers, and it is to this illustration of the two-way street between research and practice to which I now turn.

Involvement with the Policy World

A phone call I received in the late spring of 1988 — a week before my Harvard graduation — from Senator Timothy Wirth (D-Colorado), and a meeting shortly thereafter in Washington with Senator Wirth and his long-time friend and colleague, Senator John Heinz (R-Pennsylvania) led to an agreement that I would direct for them a study intended to inform the Presidential debates on environmental policy in that election year — Project 88:  Harnessing Market Forces to Protect the Environment (and a follow-up study in 1991, Project 88 — Round II, Incentives for Action: Designing Market-Based Environmental Strategies).

Many pages could be written — and, indeed, many have been written — about the influence that Project 88, sponsored by Senators Wirth and Heinz, subsequently had on policy developments at the federal level in Washington (including the path-breaking SO2 allowance trading program in the 1990 Clean Air Act amendments), within many states, and internationally in locations ranging from the European Union to China.  But my purpose in this essay is to examine the origins of my research portfolio, and so I will turn instead to reflect on the ways my experience with Project 88 (and related policy engagements with the White House, the Congress, and others) stimulated new paths of my scholarly research.

One path of research activity soon focused on normative analysis of alternative policy instruments, including work on:  transaction costs in cap-and-trade markets (Journal of Environmental Economics and Management 1995), the effects of correlated uncertainty on the choice between price and quantity instruments (Journal of Environmental Economics and Management 1996), vintage-differentiated regulations (Stanford Environmental Law Journal 2006), and policy instruments in second-best settings (with Lori Bennear, Environmental and Resource Economics 2007).  [The work on correlated uncertainty also illustrates an example of another source of research ideas, namely picking up on research by someone else, because this work was directly inspired by a footnote in Professor Martin Weitzman‘s classic work on “Prices vs. Quantities” (Review of Economic Studies 1974).]

Another area of work on normative analysis of policy instruments focused broadly on market-based instruments (with Robert Hahn, American Economic Review 1992; with Richard Newell, Journal of Regulatory Economics 2003; and the Elsevier Handbook of Environmental Economics 2003).  Other work focused more specifically on cap-and-trade systems (Journal of Economic Perspectives 1998; with Robert Hahn, Journal of Law and Economics 2011; and with Richard Schmalensee, Journal of Economic Perspectives 2013).

A conceptually distinct path of research that also found its origins in my work on Project 88 has involved examinations of the positive political economy of environmental policy (with Robert Hahn, Ecology Law Quarterly 1991; with Nathaniel Keohane and Richard Revesz, Harvard Environmental Law Review 1998; with Robert Hahn and Sheila Olmstead, Harvard Environmental Law Review 2003).

Even this extensive set of research projects and publications that derive from my work on Project 88 — depicted in the figure above — understates the influence that my work on Project 88 with Senators Wirth and Heinz has had on my scholarly research over the years.  This is because much of my work on global climate change policy, for example, has in fact focused on the potential use of market-based instruments in that realm, but for purposes of this essay, I associate that later work on climate policy with two other origins, namely, conferences and funders.

Conferences and Funders

Gradually over the 25 years since receipt of my PhD, my research has evolved from diverse work across environmental and natural resources economics, to more and more focus each year on various aspects of global climate change and related public policies.

“Climate skeptics” and other opponents of action to address climate change have sometimes accused the research community of focusing on climate change because “that is where the money is.”  Although there are sound reasons for focusing on climate change other than the availability of funds (such as the importance of the problem, and the methodological challenges it poses), there is some partial truth to the accusation.  Indeed, numerous national governments and major philanthropic foundations have made it their goal to stimulate research (and action) on climate change.

One part of my work in this realm has been research on national and sub-national climate policy instruments, often focused on the design of market-based instruments, including but not limited to cap-and-trade mechanisms (Brookings Institution 2007; Harvard Environmental Law Review 2008; Oxford Review of Economic Policy 2008; and my work on the Intergovernmental Panel on Climate Change, Second, 1995, and Third, 2001, and Fifth Assessment Reports.

An invitation from the Doris Duke Charitable Foundation to propose and eventually direct an international research and outreach project on international climate policy architecture led to much (but not all) of my work on international climate policy cooperation (with Joseph Aldy and Scott Barrett, Climate Policy 2003; with Scott Barrett, International Environmental Agreements 2003: with Sheila Olmstead, American Economic Review 2006; three books with Joseph Aldy published by Cambridge University Press 2007, 2009, 2010; an article with Judson Jaffe and Matthew Ranson, Ecology Law Quarterly 2010; and ongoing work on the IPCC Fifth Assessment Report 2010-2014; and much more).

Student Interest

Many professors who are reading this essay will not be the least bit surprised to learn that another origin of research ideas has been interest expressed by graduate students.  Three important examples stand out in my case.

One I have already written about above.  When Richard Newell (my very first PhD student) came to Harvard for graduate school in 1993, he brought with him an abiding interest in the relationship between science, technology, and policy.  At the time, Adam Jaffe and I were continuing our work on the diffusion of energy-efficiency technologies, and then the U.S. Department of Energy (DOE) solicited proposals for research that could improve the modeling of technological change in integrated assessment models of climate change (so this covers two other origins — involvement with the policy world, and potential funding).  All of this came together in a joint research initiative, funded by DOE, which supported Newell’s dissertation research on factors affecting the pace and direction of energy-efficiency technology innovation.  This led to a subsequent publication with Jaffe and Newell (Quarterly Journal of Economics 1999), as well as series of other collaborations with Newell, which are on-going to this day.

In 1999, Sheila (Cavanagh) Olmstead came to the Harvard PhD program in public policy with a strong background and keen interests in water resources and water policy.  I brought on board Michael Hanemann, then a professor at the University of California at Berkeley, as a collaborator, and together we applied (successfully) to the National Science Foundation for a grant that supported Sheila’s dissertation research on econometrically estimating demand for municipal water in the presence of block-rate pricing schedules.  Not only did that lead directly to some published work (with Olmstead and Hanemann, Journal of Environmental Economics and Management 2007), but led indirectly to other research on water pricing(with Olmstead, Water Resources Research 2009).

The work on carbon sequestration and land use described above with Ruben Lubowski and Andrew Plantinga (Journal of Environmental Economics and Management 2006; Journal of Urban Economics 2002; Land Economics 2008) also deserves mention in this part of the essay, because it all grew out of Ruben Lubowski‘s PhD dissertation research at Harvard.

Responding to Others’ Work

I mentioned above an example of picking up on someone else’s work (in a positive sense), namely a footnote in Marty Weitzman’s classic 1974 article on “Prices vs Quantities” in which he noted that he was assuming statistical independence between marginal benefits and marginal costs, which stimulated me to relax that assumption and pursue the analysis (which led to my article on the effects of correlated uncertainty in 1996 in the Journal of Environmental Economics and Management).

By contrast, sometimes researchers can be stimulated to do work in order to question others’ previous work (and related conventional wisdom).  This was the case with my collaborative work examining the topic of “corporate social responsibility,” an area of scholarship that some colleagues and I believed was populated by research and writing that generated more heat than light.  A conference we organized at Harvard led to a subsequent book that examined Environmental Protection and the Social Responsibility of Firms:  Perspectives from Law, Economics, and Business (with Harvard Law School professor, Bruce Hay, and Harvard Business School professor, Richard Vietor, 2005).  Later, I took the next step with a follow-up article with Vietor and his Harvard Business School colleague, Forest Reinhardt (Review of Environmental Economics and Policy 2008), and another with Reinhardt (Oxford Review of Economic Policy 2010).


Classroom teaching can itself provide inspiration for research.  In 2002, I was teaching a small “reading and research course” for PhD students interested in environmental economics, and lamented one day that the increasingly popular concept of “sustainability” seemed to lack a clear definition or interpretation that made sense in economic terms.  I offered a possible economic interpretation in class, and within a week, two students — Gernot Wagner and Alexander Wagner (unrelated) — had written out a mathematically formalized version of my interpretation.  We collaborated on writing a brief article that provided background as well as further exploration (Economic Letters 2003).


It may (or may not) come as a surprise that consulting (work I do outside of my Harvard responsibilities, sometimes for compensation, sometimes not) can also lead to interesting research ideas.  In my case, this has led to my thinking more carefully — with collaborators — about the analytical methods that surround net present value analysis (also called, benefit-cost analysis).

This has led to a series of papers on various dimensions of net present value analysis in the environmental realm, including such topics as:  the meaning, limits, and value of the Kaldor-Hicks criterion (with Kenneth Arrow and others, Science 1996); the role of discounting (with Lawrence Goulder, Nature 2002); new benefit-estimation methods (with Paul Portney, Journal of Risk and Uncertainty 1994; and with Lori Bennear and Alexander Wagner, Journal of Regulatory Economics 2005); and the use of Monte Carlo analysis to incorporate uncertainty in regulatory impact analysis (with Judson Jaffe, Regulation and Governance 2007).

Also, as I mentioned at the outset, my 1988 dissertation topic had grown out of some consulting work I was doing at the time for the Environmental Defense Fund.

Class Assignments

Many of my PhD students over the years have written term papers for courses that led to manuscript that were eventually published in academic journals.  But in my own case, because my PhD training in economics at Harvard did not include any courses in environmental economics (none existed at the time, as you may have noted in my previous essay, “On Becoming an Environmental Economist”), the only example I can provide of this origin of research is in a different area, namely economic history.  This is an area in which I took two wonderful courses from Professor Jeffrey Williamson (about which I wrote in my previous post).  An econometric analysis I carried out for one of those courses — “A Model of English Demographic Change: 1573-1873” was subsequently published (Explorations in Economic History 1988).

Invitations (and other origins)

There’s a clear positive correlation between the onset of grey hair and the frequency of invitations to write articles (or books) for publication.  These have included:  an article with Don Fullerton on how economists view the environment in Nature (1998); an article on common property resources in the American Economic Review (2011); my ongoing column, “An Economic Perspective” in The Environmental Forum (2006-present); my blog, “An Economic View of the Environment,” which was launched in 2009; two books of my collected works, 1988-1999 and 2000-2011 (Edward Elgar 2001, 2013); and three editions of a book of selected readings in environmental economics (W. W. Norton 2000, 2005, 2012).

Results of an Ex Post Exploration of Research Origins

Putting all of that together in a single flow chart results in the figure below, which is much clearer in a PDF version.  You can also view the entire PowerPoint presentation (you need to use Slide Show mode to see the animation) here.

As I said at the outset, I found the process of preparing this slide deck for Professor Bowles’s seminar valuable, because it enabled me to step back and reflect systematically on the origins of my research initiatives over the years and the relationships among them.  I recommend this process to other academics, because I believe it can be rewarding.  And, for academics in-the-making, that is, PhD students, I hope this essay may be informative.

On Becoming an Environmental Economist

My essay this month represents a departure from my standard blog posts about a contemporary environmental policy issue.  Rather, it is of a more personal nature, and stems from the fact that the second volume of my collected papers has just been published by Edward Elgar, Economics of Climate Change and Environmental Policy:  Selected Papers of Robert N. Stavins, 2000-2011 (2013), a successor to the first volume, published in 2000, Environmental Economics and Public Policy:  Selected Papers of Robert N. Stavins, 1988-1999.

When the publisher invited me to collect my papers in these edited volumes, it was suggested that I write a personal introduction in which I might reflect on the professional path that led to my research and writing.  I did this, and the introductory chapter of the second volume contains my latest reflections on that path.  This essay essentially consists of an abbreviated version.  My hope is that some readers will find it of interest, particularly students and others who aspire to work in this exciting and growing field.

A Professional Path

Over the past two decades, environmental and resource economics has evolved from what was once a relatively obscure application of welfare economics to a prominent field of economics in its own right.  The number of articles on the natural environment appearing in mainstream economics periodicals has continued to increase, as has the number of economics journals dedicated exclusively to environmental and resource topics.  Likewise, the influence of environmental economics on public policy has increased significantly, particularly as greater use has been made of market-based instruments for environmental protection.

In retrospect, my own professional path may now appear somewhat direct, if not altogether linear, but it hardly seemed so as I traveled along it.  The path I describe below took me back and forth across the United States and to several continents, and it took me from physics to philosophy, to agricultural extension, to international development studies, to agricultural economics, and eventually to environmental economics.  It culminated in my receipt in 1988 of a Ph.D. degree in economics at Harvard University, where I have since been a faculty member at the John F. Kennedy School of Government.  During this time, much has changed in the profession.

Early Days at Harvard

The early ascendency of the field of environmental economics, during the period from 1970 to 1990, was centered within departments of agricultural and resource economics, mainly at U.S. universities, and at Resources for the Future (RFF), the Washington research institution.  Within most economics departments, however, environmental studies remained a relatively minor area of applied welfare economics.  So, when I enrolled in the Ph.D. program in Harvard’s Department of Economics in 1983, and when I received my degree five years later, no field of study was offered in the field of environmental or resource economics.

Fortunately, Harvard permitted its graduate students to develop an optional, self-designed field as one of two “special fields” on which they were to be examined orally before proceeding to dissertation research.  Without an active environmental economist in the Department of Economics (Robert Dorfman had retired, and Martin Weitzman had yet to move to Harvard from the Massachusetts Institute of Technology), I developed an outline and reading list of the field through correspondence with leading scholars from other institutions, most prominently Kerry Smith, then at North Carolina State University.  My proposal to prepare for and be examined in the special field of environmental and resource economics (along with econometrics) was approved by the Department’s director of graduate study, Dale Jorgenson.  So began my entry into the scholarly literature.

A Nurturing Environment at Cornell

But my interest in environmental economics pre-dated by a considerable number of years my matriculation at Harvard.  Like many others before and since, I came to the field because of a personal interest in the natural environment (the origin of which I describe below).  This personal interest evolved into a professional one while I was studying for an M.S. degree in agricultural economics at Cornell University in the late 1970’s, where my thesis advisor and mentor was Kenneth Robinson.  I had originally gone to Cornell to study for a professional degree in international development, but found agricultural economics more appealing, largely because of the opportunity to examine social questions with quantitative methods within a disciplinary framework.

The faculty at Cornell and the care given to graduate students (including masters students like me) were both outstanding.  Ken Robinson, my first mentor within the economics profession, became my ongoing role model for intellectual integrity.  It was a very sad day in 2010 when Professor Robinson passed away.

A course in linear algebra, brilliantly taught by S. R. Searle, inspired me to pursue quantitative methods of analysis, and I was fortunate to then have the opportunity to study econometrics with Tim Mount.  One summer I had the great privilege of learning comparative economic systems in a small workshop setting from George Staller of the Cornell Department of Economics.   Working with Bud Stanton, I had my first experience teaching at the university level, and with Olan Forker, I had my first try at serious writing.  All of this led to research and writing of an M.S. thesis, “Forecasting the Size Distribution of Farms:  A Methodological Analysis of the Dairy Industry in New York State.”  The methodology in question was a variable Markov transition probability matrix, the cells of which were estimated econometrically in a multinomial logit framework.  Much to my surprise, this work subsequently received the Outstanding Master’s Thesis Award in the national competition of the American Agricultural Economics Association.

A Defining Move from Ithaca to Berkeley

Armed with my M.S. degree, I moved from Cornell to Berkeley, California, where I eventually met up with Phillip LeVeen, who had until shortly before that time been a faculty member in the Department of Agricultural and Resource Economics at the University of California, Berkeley.  Phil was another superb mentor, and from him I learned the power of using simple models — by which I mean a set of supply and demand curves hastily drawn on a piece of scrap paper — to develop insights into real-world policy problems.  He introduced me to a topic that was to occupy me for the next few years — California’s perpetual concerns with water allocation.  I remember many afternoons spent working with Phil at his dining room table on questions of water supply and demand.

This work with Phil LeVeen led to a consultancy and then a staff position with the Environmental Defense Fund (EDF), the national advocacy group consisting of lawyers, natural scientists, and — then almost unique among environmental advocacy organizations — economists.  At EDF, I was able to experience for the first time the use of economic analysis in pursuit of better environmental policy.  With W. R. Zach Willey, EDF’s senior economist in California, as a role model, and Thomas Graff, EDF’s senior attorney, as my mentor, I thrived in EDF’s collegial atmosphere, while thoroughly enjoying life in Berkeley’s “gourmet ghetto,” as my neighborhood was called.  Sadly, Tom Graff — without whose mentorship I would not be where I am today — passed away in 2009 after a heroic battle with cancer.

Although I found the work at EDF exceptionally rewarding, I worried that I would eventually be constrained — either within the organization or outside it — by my limited education.  So, like many others in similar situations, I considered a law degree as the next logical step.  In fact, I came very close to enrolling at Stanford Law School, but instead, in 1983, I accepted an offer of admission to the Department of Economics at Harvard, moved back east to Cambridge, Massachusetts, and began what has turned out to be a long-term relationship with the University.

Origins of Interest in Environmental Economics

But where did my interest in the natural environment begin?  Not at Cornell; it was present long before those days.  But it had not yet arisen when I was studying earlier at Northwestern University, from which I received a B.A. degree in philosophy, having departed from my first scholarly interest, astronomy and astrophysics.

Rather, the origins of my affinity for the natural environment and my interest in resource issues are to be found in the four years I spent in a small, remote village in Sierra Leone, West Africa, as a Peace Corps Volunteer, working in agricultural extension (in particular, paddy rice development).  It was there that I was first exposed both to the qualities of a pristine natural environment and the trade-offs associated with economic development.

So, I had begun in astrophysics, moved to philosophy (both at Northwestern), then to agricultural extension in a developing country (Sierra Leone), then to international development studies and subsequently to agricultural economics (both at Cornell), then to environmental economics and policy (EDF), and eventually to graduate study in economics at Harvard.

From Berkeley to Cambridge

My dissertation research at Harvard was directed by a committee of three faculty members:  Joseph Kalt, Zvi Griliches, and Adam Jaffe.  Joseph Kalt was the first faculty member at the Department of Economics to validate my interest in environmental and resource issues, and he was unfailingly generous to me and many other graduate students in making his office (and computer, then a rather scarce resource) available at all hours.  Now a colleague at the Kennedy School, Joe provided examples never to be forgotten — that economics could be a meaningful and enjoyable pursuit, and that excellence in teaching was a laudable goal.

Zvi Griliches was not only my advisor and mentor, but my spiritual father as well.  Generations of Harvard graduate students would offer similar testimony.  My own father had died only a year before I entered Harvard, and Zvi soon filled for me many paternal needs.  It is now more than a decade since Zvi himself passed away.  I felt as if I had lost my father a second time.

If Zvi Griliches provided caring and inspiration, Adam Jaffe provided invaluable day-to-day guidance.  It was Adam who convinced me not to go on the job market in my fourth year with what would have been a mediocre dissertation, but to put in another year and do it right.  That turned out to be some of the best professional advice I have ever received.  Our intensive faculty-student relationship from dissertation days subsequently evolved into a very productive professional (and personal) one that continues to this day.  The name of Adam Jaffe appears frequently in my curriculum vitae as a co-author; he has been and continues to be much more than that.

Although they were not members of my thesis committee, I should acknowledge two other faculty members at the Harvard Department of Economics who played important roles in my education.  I was fortunate to take two courses in economic history (a department requirement) from Jeffrey Williamson, who had recently arrived from the University of Wisconsin.  Williamson’s class sessions were as close as anything I have witnessed to being an economic research laboratory.  In class after class, we would carefully dissect one or more articles — examining hypothesis, theoretical model, data, estimation method, results, and conclusions.  If there was any place where I actually learned how to carry out economic research, it was in those classes.

The other name that is important to highlight is that of Lawrence Goulder, then a faculty member at Harvard, and now a professor at Stanford.  I say this not simply because he was willing to be my examiner in my chosen field of environmental and resource economics, nor because he subsequently became such a close friend.  Rather, what is striking about my professional relationship with Larry is the degree to which he has been an unnamed collaborator on so many projects of mine.  Although he and I have co-authored no more than a few articles, his name probably appears more frequently than anyone else’s in the acknowledgments of papers I have written.  There is no one whose overall judgement in matters of economics I trust more, and no one who has been more helpful.

First Steps for a Newly-Minted Ph.D. Recipient

When I began graduate school at Harvard in 1983, it was my intention to return to EDF as soon as I received my degree.  But by my third year in the program, I had decided to pursue an academic career, although one that was heavily flavored with involvement in the real world of public policy.  Within the context of this professional objective, it was not a difficult decision to accept the offer I received in February, 1988, to become an Assistant Professor at the Kennedy School.  Although some of the other offers I received at that time were also very attractive, the choice for me was obvious, and I have never regretted it — not for a moment.

I remain at the Kennedy School today, where I was promoted to Associate Professor in 1992 (an untenured rank at Harvard), and to a tenured position as Professor of Public Policy in 1997.   In 1998, I accepted an appointment as the Albert Pratt Professor of Business and Government.

Twenty-Five Years on the Harvard Faculty

Two years later, I launched the Harvard Environmental Economics Program, which today brings together — from across the University — thirty Faculty Fellows and twenty-five Pre-Doctoral Fellows, who are graduate students studying for the Ph.D. degree in economics, political economy and government, public policy, or health policy.  The Program, which I continue to direct, forms links among faculty and graduate students engaged in research, teaching, and outreach in environmental, natural resource, and energy economics and related public policy, by sponsoring research projects, convening workshops, and supporting graduate (and undergraduate) education.

A key reason why the Program — and its various projects, including the Harvard Project on Climate Agreements — have been so successful is the superb administrative leadership and staff support  it enjoys.  Everyone who has been involved in virtually any way has come away impressed by our Executive Director, Robert Stowe, and Program Manager, Jason Chapman.

At the Kennedy School, I have had an excellent mentor, William Hogan, and a superb advisor and friend, Richard Zeckhauser.  Over the years, five successive deans have provided leadership, guidance, and support (including abundant time for my research and writing) — Graham Allison, Robert Putnam, Albert Carnesale, Joseph Nye, and David Ellwood.  At Harvard more broadly, I have benefitted from regular interactions with Daniel Schrag, director of the Harvard University Center for the Environment, and Martin Weitzman of the Department of Economics.  For two decades, Marty and I have co-directed a bi-weekly Seminar in Environmental Economics and Policy, which has provided me with frequent opportunities to learn both from seminar speakers and from Marty’s questions and comments.  I will refrain from naming the many others at Harvard and elsewhere from whom I continue to learn — including my many co-authors — only because the list of such valued colleagues and friends is so long.  Included have been a most remarkable set of Ph.D. students, many of whom have gone on to productive — indeed illustrious — careers.

Along the way, I have had my share of administrative responsibilities at Harvard, including serving as Director of Graduate Studies for the Doctoral Program in Public Policy and the Doctoral Program in Political Economy and Government, and Co-Chair of the Harvard Business School-Harvard Kennedy School Joint Degree Programs.  Outside of Harvard, I have had the privilege of being a University Fellow of Resources for the Future, a Research Associate of the National Bureau of Economic Research, and the founding Editor and now Co-Editor of the Review of Environmental Economics and Policy, as well as a member of the Board of Directors of Resources for the Future, the Scientific Advisory Board of the Fondazione Eni Enrico Mattei, and numerous editorial boards. I must also note that I serve as an editor of the Journal of Wine Economics.  In 2009, I was elected a Fellow of the Association of Environmental and Resource Economists.

Working with the “Real World”

What originally attracted me to the Kennedy School was the possibility of combining an academic career with extensive involvement in the development of public policy.  I have not been disappointed.  Indeed, a theme that emerges from my collected papers is the interplay between scholarly economic research and implementation in real-world political contexts.  This is a two-way street.   In some cases, my policy involvement has come from expertise I developed through research, following a path well worn by academics.  But, in many other cases, my participation in policy matters has stimulated for me entirely new lines of inquiry.

What I have characterized as involvement in policy matters is described at the Kennedy School as faculty outreach, recognized to be of great institutional and social value, along with the two other components of our three-legged professional stool — research and teaching.  Because they relate to a number of the papers collected in this volume, I should note that my outreach efforts fall into five broad categories:  advisory work with members of Congress and the White House (for example, Project 88, a bipartisan effort co-chaired by former Senator Timothy Wirth and the late Senator John Heinz, to develop innovative approaches to environmental and resource problems); service on federal government panels (for example, my role as Chairman of the Environmental Economics Advisory Committee of the U.S. Environmental Protection Agency Science Advisory Board); on-going consulting — often on an informal basis — with environmental NGOs (most frequently, the Environmental Defense Fund) and private firms; advisory work with state governments; and professional interventions in the international sphere, such as service as a Lead Author for the Second and the Third Assessment Reports and a Coordinating Lead Author for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, professional roles with the World Bank and other international organizations, and advisory work with foreign governments.

Finally, because my two books of collected papers focus on my articles, not my books, I should note that over the years I have been privileged to be co-editor with Joseph Aldy of Post-Kyoto International Climate Policy:  Implementing Architectures for Agreement (Cambridge University Press, 2010), Post-Kyoto International Climate Policy:  Summary for Policymakers (Cambridge University Press, 2009), and Architectures for Agreement: Addressing Global Climate Change in the Post-Kyoto World (Cambridge University Press, 2007); editor of three editions of Economics of the Environment (W. W. Norton, 2000, 2005, 2012); co-editor with Bruce Hay and Richard Vietor of Environmental Protection and the Social Responsibility of Firms:  Perspectives from Law, Economics, and Business (Resources for the Future, 2005); editor of The Political Economy of Environmental Regulation (Edward Elgar, 2004), co-editor with Paul Portney of Public Policies for Environmental Protection (Resources for the Future, 2000); and author of Environmental Economics and Public Policy: Selected Papers of Robert N. Stavins, 1988-1999 (Edward Elgar, 2000).

The New Volume

That last book is the predecessor of the new volume.  Whereas the first volume (Stavins 2000) included selected papers from the period 1988 through 1999, the second volume covers the period from 2000 through 2011.  To prepare this new book, I selected 26 articles from the (many more) published papers I wrote  — frequently with co-authors — over the past decade.  Making this selection was not an easy task, but it was a rewarding one, because choosing the papers and organizing them has forced me to step back and reflect on the set of research endeavors in which I have been engaged over this decade, and thus to think more clearly about current and possible future directions.

The book is divided into seven parts.  The papers in Part I provide an overview of environmental and resource economics, treating broadly several key topics, including economic views of:  the problem of the commons (Stavins, American Economic Review, 2011); the history of U.S. environmental regulation (Hahn, Olmstead, and Stavins, Harvard Environmental Law Review, 2003); and corporate social responsibility (Reinhardt, Stavins, and Vietor, Review of Environmental Economics and Policy, 2008).

The articles in Part II deal with methods of environmental policy analysis, focusing, respectively, on:  interpreting sustainability in economic terms (Stavins, Wagner, and Wagner, Economic Letters, 2003); the use of discounting in net present value analysis (Goulder and Stavins, Nature, 2002); the development of a new revealed-preference method for inferring environmental benefits (Bennear, Stavins, and Wagner, Journal of Regulatory Economics, 2005); and the value of formal assessment of uncertainty (that is, Monte Carlo analysis) in regulatory impact analysis (Jaffe and Stavins, Regulation and Governance, 2007).

Part III turns to economic analysis of alternative environmental policy instruments, with examinations of: vintage-differentiated environmental regulation (Stavins, Stanford Environmental Law Journal, 2006); cost heterogeneity and the potential savings from employing market-based environmental policies (Newell and Stavins, Journal of Regulatory Economics, 2003); the effects of allowance allocations on the performance of cap-and-trade systems (Hahn and Stavins, Journal of Law and Economics, 2011); and second-best theory and the use of multiple policy instruments (Bennear and Stavins, Environmental and Resource Economics, 2007).

Part IV focuses on a topic that also received considerable treatment in the predecessor to this volume, namely the economics of technological change.  Here the articles include: a survey of the literature on environmental policy and technological change (Jaffe, Newell, and Stavins, Environmental and Resource Economics, 2002); an analysis of the interaction of environmental and technological market failures (Jaffe, Newell, and Stavins, Ecological Economics, 2005); an empirical assessment of the effect of environmental regulation on technology diffusion in the case of chlorine manufacturing (Miller, Snyder, and Stavins, American Economic Review Papers and Proceedings, 2003); and the effects of economic and policy incentives on carbon mitigation technologies (Jaffe, Newell, and Stavins, Energy Economics, 2006).

Part V consists of three articles in the area of natural resource economics dealing with land and water resources:  an analysis of the factors driving land-use change in the United States (Lubowski, Plantinga, and Stavins, Land Economics, 2008); an econometric examination of the significance of terroir, the notion that wine quality is primarily determined by location (Cross, Plantinga, and Stavins, American Economic Review Papers and Proceedings, 2011); and an assessment of urban water demand under alternative pricing structures (Olmstead, Hanemann, and Stavins, Journal of Environmental Economics and Management, 2007).

Part VI consists of four articles on domestic (national and sub-national) climate change policy, beginning with a description and assessment of a comprehensive U.S. cap-and-trade system for carbon dioxide and other greenhouse gas emissions (Stavins, Oxford Review of Economic Policy, 2008), and followed by:  an examination of the interactions of national and sub-national climate policies (Goulder and Stavins, American Economic Review Papers and Proceedings, 2011); an econometric study of the carbon-sequestration supply function (Lubowski, Plantinga, and Stavins, Journal of Environmental Economics and Management, 2006); and an assessment of the factors that affect the costs of biological carbon sequestration (Newell and Stavins, Journal of Environmental Economics and Management, 2000).

Finally, Part VII focuses on the international dimensions of climate change policy, and consists of four articles:  a comparison of alternative global climate change policy architectures (Aldy, Barrett, and Stavins, Climate Policy, 2003); an assessment of the Kyoto Protocol (Stavins, Milken Institute Review, 2005); an examination of a promising post-Kyoto international climate regime (Olmstead and Stavins, American Economic Review Papers and Proceedings, 2006); and a detailed examination of a key element of emerging international climate policy architecture, namely the linkage of regional, national, and sub-national tradable permit systems (Ranson, Jaffe, and Stavins, Ecology Law Quarterly, 2010).

Reflections on Common Themes

Selecting the essays for this second volume of my papers permitted me to take note of some common themes that emerge from this decade of research and writing.  First, there is the value — or at least, the potential value — of economic analysis of environmental policy.  The cause of virtually all environmental problems in a market economy is economic behavior (that is, imperfect markets affected by externalities), and so economics offers a powerful lens through which to view environmental problems, and therefore a potentially effective set of analytical tools for designing and evaluating environmental policies.

A second message, connected with the first, is the specific value of benefit-cost analysis for helping to promote efficient policies.  Economic efficiency ought to be one of the key criteria for evaluating proposed and existing environmental policies.  Despite its limitations, benefit-cost analysis can be useful for consistently assimilating the disparate information that is pertinent to sound decision making.  If properly done, it can be of considerable help to public officials when they seek to establish or assess environmental goals.

Third, the means governments use to achieve environmental objectives matter greatly, because different policy instruments have very different implications along a number of dimensions, including abatement costs in both the short and the long term.  Market-based instruments are particularly attractive in this regard.

Fourth, an economic perspective is also of considerable value when reflecting on the use of natural resources, whether land, water, fisheries, or forests.  Excessive rates of depletion of these resources are frequently due to the nature of the respective property-rights regimes, in particular, common property and open-access.  Economic instruments — such as ITQ systems in the case of fisheries — can and have been employed to bring harvesting rates down to socially efficient levels.

Fifth and finally, policies for addressing global climate change — linked with emissions of carbon dioxide and other greenhouse gases — can benefit greatly from the application of economic thinking.  On the one hand, the long time-horizon of climate change, the profound uncertainty in links between emissions and actual damages, and the possibility of catastrophic climate change present significant challenges to conventional economic analysis.  But, at the same time, the ubiquity of energy generation and use in modern economies means that only market-based policies — essentially carbon pricing regimes — are feasible instruments for achieving truly meaningful emissions reductions.  Hence, despite the challenges, an economic perspective on this grandest of environmental threats is essential.

Final Words

On a personal level, the professional path I have taken offers some confirmation that research can influence public policy, and it also illustrates that involvement in public policy can stimulate new research.  The quest — both professional and personal — that took me from Evanston, Illinois, to Sierra Leone, West Africa, to Ithaca, New York, to Berkeley, California, and finally to Cambridge, Massachusetts suggests some consistency of purpose and even function.  I continue to find myself doing similar things, but in different contexts.  It is fair to say that my professional life has taken me along a path that has brought me home.  The words of T. S. Eliot (1943) ring true:

                                        We shall not cease from exploration
                                        And the end of all our exploring
                                        Will be to arrive where we started
                                        And know the place for the first time.

Selecting the papers for this volume forces me to reflect on the past and think more clearly about the future.  The twenty-six articles that comprise this book and the twenty-two essays that comprised the predecessor volume are the product of twenty-three wonderful years on the faculty of the Harvard Kennedy School.  During this time, I have continued to learn about environmental economics and related public policy from colleagues, collaborators, students, friends, and inhabitants of the ”real world” of public policy, individuals from government, private industry, advocacy groups, and the press.  I hope that my learning will continue.

The Credit Downgrade and the Congress: Why Polarized Politics Paralyze Public Policy

There’s room for debate about whether U.S. government deficits justify Standard & Poor’s downgrading last week of long-term U.S. debt, but the more important factor cited in S&P’s report is that “the effectiveness, stability, and predictability of American policymaking and political institutions have weakened…” The S&P team emphasizes that “the difficulties in bridging the gulf between the political parties … makes us pessimistic about the capacity of Congress and the Administration” to address the crucial problems the country faces.

Although these S&P judgments were intended to refer exclusively to fiscal policy, they really apply to a much broader set of issues, ranging from economic to health to environmental policies. The key reality is this: there is a widening gulf between the two political parties that is paralyzing sensible policy action.

Political Polarization

This increasing polarization between the political parties has shown up in a number of studies by political scientists employing a diverse set of measures that place roll-call votes by members of Congress on an ideological spectrum from extreme right to extreme left. This polarization – the disappearance of moderates – has been taking place for four decades. The rise of the Tea Party movement within the Republican Party is only the most recent vehicle that has continued a 40-year trend.

Why has this collapse of the middle taken place; why has party polarization increased so dramatically in the Congress over the past 40 years? In my view, three structural factors stand out.

Three Structural Factors

First, there has been the increasing importance of the primary system, a consequence of the “democratization” of the nomination process that took flight in the 1970s. A small share of the electorate vote in primaries, namely those with the strongest political preferences – the most conservative Republicans and the most liberal Democrats. This self-selection greatly favors candidates from the extremes.

Second, decades of redistricting – a state prerogative guaranteed by the Constitution – has produced more and more districts that are dominated by either Republican or Democratic voters. This increases the importance of primary elections, which is where the key choices among candidates are now made in many Congressional districts. Because of this, polarization has proceeded at a much more rapid pace in the House than in the Senate.

Third, the increasing cost of electoral campaigns greatly favors incumbents (with the ratio of average incumbent-to-challenger financing now exceeding 10-to-1). This tends to make districts relatively safe for the party that controls the seat, thereby increasing the importance of primaries.

These three factors operate mainly through the replacement of members of Congress (whether due to death, retirement, or challenges from within the party) – that is, the ideological shifts that cause increasing polarization largely occur when new members are elected (from either party, although a disproportionate share of polarization has been due to the rightward shift of new Republicans).

To a lesser degree, polarization has also taken place through the adaptation of sitting members of Congress as they behave more ideologically once in office. Such political conversions are due to the same pressures noted above: in order to discourage or survive primary challenges, Republican members shift rightward and Democratic members shift leftward.

A recent case in point is Senator John McCain, Republican of Arizona, who evolved from being a moderate at the time of his 2008 Presidential run to being a solid conservative in 2010, in response to a primary challenge from a Tea Party candidate.

Long-Term Implications

If the increasing polarization of the Congress is due to these factors, then it is difficult to be very optimistic about the prognosis in the near term for American politics. This is because it is unlikely that any of these factors will soon reverse course.

The two parties are not about to abandon the primary system to return to smoke‑filled back rooms. Likewise, no state legislature is willing to abandon its power to redistrict. And public financing of campaigns and other measures that would reduce the advantages of incumbency remain generally unpopular (among incumbents, who would – after all – need to vote for such reforms).

Other Factors?

True enough, in addition to these long-term structural factors that have driven political polarization, shorter-term economic and social fluctuations have also had pronounced effects. In particular, significant economic downturns – whether the Great Depression of the 1930s or the Great Recession of the past several years – increase political polarization.

The 1930s saw not only the rise of American socialists and communists, but also the rise of American right-wing extremism. It took World War II to bring an end both to the economic upheaval of the 1930s and the destructive political polarization that had accompanied it.

U.S. participation in the war brought a degree of political unity at home, largely because U.S. action was precipitated by the attack on Pearl Harbor. Under conditions of less clear motivation for U.S. military action abroad – such as the war in Vietnam – the result has not been political unity, but divisiveness and polarization. The ultimate impacts on domestic politics of the wars in Afghanistan and Iraq may hinge on whether they are perceived to be patriotic responses to a foreign attack (9/11) or the latest manifestations of U.S. military adventurism.

The Future

So, it’s reasonable to anticipate – or at least to hope – that better economic times will reduce the pace of ongoing political polarization. However, in the face of the three long-term structural factors I’ve identified above – the increasing importance of primaries, continuing redistricting, and the increasing costs of electoral campaigns – it is difficult to be optimistic about the long-term prognosis for American politics.

No matter how one feels about the wisdom of Standard & Poor’s downgrading of long-term U.S. debt, the issue of greater concern should be their assessment of the state of the U.S. body politic.