Transatlantic differences on the use of force reached their post-cold war high point around the time of the 2003 Iraq War, which European publics overwhelmingly opposed. In the aftermath of the Iraq crisis, there seemed to be some truth to Robert Kagan’s claim (Of Paradise and Power, 2003) that “Americans are from Mars and Europeans are from Venus” when it comes to determining threats, setting priorities, and devising policy responses in the field of national security. More than a decade after the initial invasion of Iraq, Philip Everts and Pierangelo Isernia set out to reassess Kagan’s argument that Americans and Europeans have fundamentally different perspectives on foreign affairs and the use of force in particular. “We are now in a better position to see,” the authors explain at the outset of this valuable new book, “what is structural in the differences between Europeans and Americans and what turns out to have been merely transitory” (p. 3).

There is no dearth of research on public opinion and the international use of force, especially in the American context. But relatively few studies have examined the issue from an explicitly transatlantic perspective, comparing and contrasting American and European attitudes. The few notable exceptions include Everts and Isernia’s own journal articles and edited volumes over the last fifteen years or so. In the book under review, the authors provide a summary and interpretation of recent survey data, mainly from the 2002–2009 period. The data examined are derived primarily from the Transatlantic Trends surveys that have been conducted annually since 2003 under the auspices of the German Marshall Fund for the United States, and to a lesser degree from PEW Global and Eurobarometer surveys.

Against Kagan, Everts and Isernia insist that a common transatlantic worldview, or “transatlantic order,” does exist and has proved quite resilient. In their assessment, this order rests on four pillars: 1) a shared definition of external threats; 2) a sense of community; 3) support for the main transatlantic institutions, with NATO at the core; and (4) a willingness to use force to defend this order if needed. The authors acknowledge that in 2002, soon after the 9/11 terrorist attacks, there was a significant transatlantic gap in threat perceptions. A far greater percentage of Americans (92%) than Europeans (65%) considered international terrorism to be a “critical threat,” and Europeans generally expressed less concern about a variety of other potential threats. But the gap narrowed in subsequent years, as threat perceptions gradually declined among Americans. Regarding the sense of transatlantic community as measured by mutual “favorability” ratings, the authors note that it suffered significantly as a consequence of the Iraq War, but favorability ratings increased again over the following years. Finally, although Europeans became markedly less supportive of American leadership and transatlantic institutions during the presidency of George W. Bush, European support for both by-and-large moved back to pre-2002 levels once a new U.S. administration took office in 2009.

However, Everts and Isernia recognize that notable transatlantic differences have continued to exist on the question of what to do about various international challenges. Americans have remained significantly more likely than Europeans to support the use of military force to address some of those challenges, by a margin of up to 20 percent in some years. According to the authors, this does not necessarily indicate that Europeans are pacifist; European audiences simply appear to be more pessimistic about the ability of military intervention to achieve desirable outcomes, especially when it comes to combating terrorism and nuclear proliferation.

Consistent with other studies, Everts and Isernia find that multilateralism generally increases public support for military intervention on both sides of the Atlantic. But there are important differences: Americans primarily want burden sharing with partners in international coalitions; Europeans, by contrast, attach greater importance to approval by the UN Security Council and value the resulting legitimacy as an end in itself. Focusing on the Kosovo, Afghanistan, and Iraq wars, the authors also provide valuable insights about the influence of time on public support for military operations. To the extent that a rally-‘round-the-flag effect that boosts public support after the initiation of hostilities does exist, they find, it is usually short-lived. Also, perhaps unsurprisingly, public support for lower-risk air strikes tends to be more enduring on both sides of the Atlantic than support for ground combat, especially when the latter involves significant casualties. Finally, the public in traditionally “Atlanticist” countries such as the UK, the Netherlands, and Denmark is markedly more supportive of (participation in) U.S.-led military operations, especially when they turn out to be protracted, than the public in other European countries.

Everts and Isernia also present some interesting findings on how political ideology influences attitudes toward transatlantic cooperation, including on the use of force, in Europe and the United States. In Europe, those on the political left are slightly less pro-American and less Atlanticist (as well as generally more dovish) than those on the right; meanwhile, in the United States the left is more pro-European and Atlanticist than the right. Democrats and Independents in the United States are quite close to the European mainstream in their worldview and attitudes toward the use of force. To the extent that a serious and potentially consequential transatlantic gap does exist, therefore, it is to be found between American conservatives and the European mainstream. Everts and Isernia conclude from their analysis that a contentious climate in transatlantic relations is especially likely to emerge when a) a right-wing government in the United States is willing to use force unilaterally, b) Atlanticists in Europe are not mobilized or even critical of the United States, and c) European governments are center-left.

This book makes a welcome contribution to mapping transatlantic similarities and differences in threat assessment and support for the use of force. At the same time, there are some important limitations having to do primarily with the book’s temporal and geographic focus. The analysis relies heavily on data from the 2002–2006 period, and there is hardly any discussion (or indeed presentation) of data from the 2010–2015 period. In particular, there is no discussion of public attitudes toward recent military interventions in Libya and Syria. Furthermore, the data on Europe is heavily biased toward a few western European countries, mainly the United Kingdom, France, Germany, Italy, and the Netherlands. The book thus largely amounts to an investigation of the short- and medium-term impact of the 2003 Iraq War on transatlantic attitudes toward security cooperation and the use of force. The authors' finding that the estrangement over Iraq did not result in lasting damage to the transatlantic relationship, at least as far as public attitudes are concerned, is an important one—but it also makes the argument and analysis appear somewhat dated.

Transatlantic opinion on the use of force has evolved significantly in recent years. Following protracted involvements in Afghanistan and Iraq, Americans have become more reluctant to support large-scale military involvements overseas. Meanwhile, as terrorism has become an increasingly real threat for European societies, recent opinion polls suggest that Europeans have become somewhat more willing to support the use of force. As of late 2015, for instance, majorities in both Britain and France supported their countries’ participation in military action against “Islamic state” militants in Syria. In France in particular, a country that has not been suffering from an Iraq syndrome, the public has been surprisingly willing to follow political elites in supporting military intervention—whether in Libya, Syria, Mali, or the Central African Republic. This has paradoxically brought public attitudes on the use of force in the one western European country that was most “anti-American” in the run-up to the 2003 Iraq War to be most closely aligned with those of the (still quite hawkish) American mainstream today. It is to be hoped that Everts and Isernia will provide valuable insights on these more recent developments in their future publications.