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Steven Hurst 80x108Andrew Wroe 80x108Contemporary politics in America have become riven by the high level of partisan polarization between the Republican and Democratic parties. But has this polarization had an impact on foreign policy? In new research that analysis votes in the U.S. House of Representatives over the past 40 years, Steven Hurst and Andrew Wroe find that while the House was polarized on foreign policy issues after the 1970s, this largely disappeared by the early 2000s, only to reappear more recently. With this in mind, they argue that more sophisticated models are needed to capture the effects of partisan polarization on foreign policy. 

It is generally accepted that contemporary American politics is now characterized by high levels of partisan polarization (an increasingly deep ideological divide between the two main parties).  It is also widely agreed that this has had deeply negative consequences for the conduct of US domestic politics.

Less attention has been paid to the impact of polarization on foreign policy-making, though it is potentially equally severe.  Since 1945 US foreign policy has been based on a liberal internationalist consensus blending cooperative/consensual elements (support for international institutions, foreign assistance, and free trade) with coercive ones (defence spending, military superiority, and the use of force). This consensus has been sustained by the dominance of both parties by centrist politicians who recognize the necessity of both dimensions to a successful foreign policy.

Increasing partisan polarization, however, has led to fears that the centre ground is being abandoned, with Democrats backing only the consensual tools of foreign policy whilst Republicans reject them in favour of a reliance on coercion. The potential consequences of that development are the collapse of liberal internationalism and its replacement by a foreign policy characterised by deep swings between cooperative and hardline policies as Democrats and Republicans alternate in power and/or increasing foreign policy gridlock as the partisan opposition in Congress seeks to block presidential initiatives.  Both outcomes would clearly have significant consequences for the ability of the US to construct a coherent foreign policy.

The potential consequences of polarization for foreign policy, however, depend on its actually existing in the first place, and while there is a broad consensus that domestic politics are polarized, there is a marked divide between those who believe that partisan polarization has become the foreign policy norm, and those who argue that the liberal-internationalist consensus remains intact.

Credit: DonkeyHotey (Flickr, CC-BY-2.0)

Credit: DonkeyHotey (Flickr, CC-BY-2.0)

In order to evaluate the consequences of polarization for US foreign policy, it is first necessary to develop an accurate picture of the extent to which policy-making behaviour is, or is not, polarized. With this in mind, we re-examined the most contentious aspect of this debate: voting behavior in Congress.

We analysed votes in the House of Representatives between 1970 (after which it is alleged that foreign policy polarization began to increase) and 2013 utilising a variety of indicators. Firstly, we employed the standard indicator utilised in most studies of polarization, the party unity vote, which measures the percentage of time in each year that a majority of Democrats opposed a majority of Republicans on foreign policy votes. In addition, we measured the level of party unity votes on foreign policy relative to domestic policy on the assumption that if levels of unity on the former increasingly approached those on the latter this would indicate increasing polarization. Thirdly, we ran the analysis looking only at votes on which the president had expressed a position.  A key criticism of the argument that polarization now characterizes congressional foreign policy voting is that this is simply a methodological consequence of including all votes, whether important or trivial, in the analysis. By using only presidential position votes we were able to test this claim (presidents rarely express a position on unimportant legislation). Finally, we employed a static indicator which measured whether Congress was polarized at any  specific point in time.

When we ran the analysis we found that the analyses of party unity using all votes on the one hand and only presidential position votes on the other both tell a similar story of an initial increase in polarization through the 1970s and into the 1980s, a levelling off and subsequent decline in polarization from the late 1980s, followed by a another upturn in polarization from the mid 2000s.

The comparison of domestic and foreign policy voting was equally inconclusive. In the 1970s, foreign policy voting was increasingly more partisan than domestic policy voting. The difference declined gradually in the 1980s and partisanship on foreign issues fell back towards the levels of partisanship on domestic issues in the 1990s. The new century witnessed a continuation of this trend only for it to turn back towards partisanship once again in the late Bush and Obama presidencies.

The analysis examining foreign policy polarization at specific points in time returns similarly complex results. The analysis utilising presidential position votes demonstrates that House voting on foreign policy issues has been polarized for a clear majority of the time since 1970 while the analysis of all votes shows polarization becoming the exception rather than the rule since 2000.

Our conclusion, therefore, is that the existing alternatives presented in the literature on foreign policy polarization—new norm or myth—are too simplistically drawn. Congress is not polarized or polarizing on foreign policy issues; nor is it not polarized or becoming less polarized.

What remains is the problem of accounting for this rather complex set of results. Two potential lines of analysis suggest themselves. Either, against most existing arguments, the causes of polarization are not permanent and ongoing but rather fluctuate over time, or more likely, the effects of polarization are qualified by those of one or more intervening variables (divided government, partisan identity of the president, economic growth levels, the changing issue agenda). If it is the latter, then we need to develop more sophisticated models in order accurately to capture the effects of partisan polarization on foreign policy.

This article is based on a talk given at the LSE US Foreign Policy Conference held on September 17-19th, 2014. You can watch video highlights from the conference in the player below:

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Note:  This article gives the views of the author, and not the position of U.S.App– American Politics and Policy, nor of the London School of Economics.

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About the authors 

Steven Hurst 80x108Steven Hurst – Manchester Metropolitan University
Steven Hurst is in the Department of History, Politics & Philosophy at Manchester Metropolitan University. His research specialism is the foreign policy of the United States since 1945. 



Andrew Wroe 80x108Andrew Wroe – University of Kent
Andrew Wroe is a lecturer in American politics at the University of Kent. His current research interests focus on the trust in government, particularly the reasons for its decline and its effects on the wider polity. Recent work has focused on how low levels of political trust frame citizens’ perceptions of elected officials and may actually help engender political scandals.