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Henry Kissinger: An Occasional Realist

He is neither a consistent nor a profound realist thinker. For that, we should look to Hans Morgenthau.

Barry Gewen, The Inevitability of Tragedy: Henry Kissinger and His World (New York: W.W. Norton, 2020), 480 pages.

New York Times book review editor Barry Gewen is right that we can only understand today’s world through an intellectual framework that emphasizes power and cautions against excessive optimism about our ability to transform the often-tragic character of international politics. He proposes in The Inevitability of Tragedy that realism is the clearest lens through which to view the complexity of the 21st century, and the surest guide for American foreign policy.

Gewen’s recognition that realism remains relevant is refreshing because it seems not so long ago that proponents (and critics) of the post-Cold War liberal global order were declaring the “end of history.” The U.S.-Soviet rivalry ended not with a bang but with a whimper. Democracy appeared to take root in its ashes, free markets blossomed, and the dog-eat-dog world of international politics seemed to have been tamed by a tight web of international institutions. Today, the global and even domestic fortunes of democracy seem bleak, free trade is out of fashion, and international institutions from the European Union to the World Health Organization are on life support. The ism of the day is not liberalism but realism.

If realism is ascendant today, then, should not its most famous adherent, former national security adviser, secretary of state, and ubiquitous adviser to presidents Henry Kissinger, be our teacher and guide? Gewen says “yes,” lauding Kissinger as a “philosopher of international relations who has much to teach us about how the modern world works—and doesn’t. His arguments for his brand of realism—thinking in terms of national interest and the balance of power—offer the possibility of rationality, coherence, and a necessary long-term perspective at a time when all three of these qualities seem to be in short supply.” 

Just because realism is (or ought to be) resurgent does not mean that Kissinger should be our guide. Upon close inspection, he turns out to be neither a consistent nor a profound realist thinker. For that we should look to Hans Morgenthau and to the rich lode of subsequent realist thought that owes far more to him than to Kissinger. Readers will likely finish Gewen’s biography convinced that Kissinger’s genius was not so much how to understand and conduct relations among states but how to get as close to power in the U.S. government as often as he could. 

To move closer to power in Cold War and post-Cold War America required compromises of principle and intellectual consistency. Not surprisingly, therefore, Kissinger’s commitment to realism has been at best episodic. Despite the American establishment’s fixation with power, liberalism rather than realism has of late provided the blueprint for how to use it. No wonder that Kissinger has been at best an occasional realist.

Kissinger’s Strange Intellectual Bedfellows

Not content to praise Kissinger as a distinguished scholar and prominent statesman, Gewen also calls him a “philosopher” and connects him to such eminent 20th century thinkers as Hannah Arendt, Leo Strauss, and Morgenthau. To be sure, all were German Jews who fled Europe after Hitler’s ascent to power. But does Kissinger belong in this intellectual pantheon?

He was a child of 10 when he left Germany. Despite his accent, which cynics suspect was more affected than real, he was thoroughly American. The others grew up in Europe and lived there as politically aware and engaged adults through the collapse of the Weimar Republic and the dawn of the Third Reich.

The four also had fundamentally different educations. Arendt, Strauss, and Morgenthau were schooled in a continental intellectual milieu permeated by the thought of intellectual giants like Friedrich Nietzsche and Max Weber, and they directly engaged with some of the most important and controversial German thinkers of the day, including Hans Kelsen, Karl Jaspers, Martin Heidegger, and Carl Schmitt. Kissinger was well educated by American lights. He studied accounting at New York’s City College before the Second World War and government at Harvard after the war, where he studied with professors like William Yandell Elliot, who were hardly intellectual luminaries. In short, his education was hardly comparable to the one the other three received.

What most distinguishes Kissinger from Arendt, Strauss, and Morgenthau, however, is that the latter were major thinkers who produced truly important bodies of theoretical work that explain how the world works. Kissinger did not. To be sure, he penned some useful historical works early in his career—particularly his book on Metternich and Castlereagh and an essay on Bismarck—but his career was not a comparable, intellectual tour de force.

That was probably the case because Strauss, Arendt, and Morgenthau were primarily scholars while Kissinger spent most of his life trying to get out of the Ivory Tower and into the corridors of power. The difference in their mindsets is reflected in Gewen’s account. Strauss and Arendt, he writes, were the “ultimate iconoclasts, subversive by their very nature, because social and political activity was based upon popular opinion, public dogma, and unexamined tradition, whereas philosophy existed to scrutinize all opinions, dogmas, and traditions.” Kissinger, in contrast, has led the life of the consummate insider.

True, Kissinger fancies himself something of a philosopher-king, an individual who combined the most rarified level of thought with effective action. But as Plato famously taught in The Republic, philosophizing and ruling were radically different enterprises and not likely to be successfully combined in any individual. A better reader of Plato, Morgenthau warned in a 1973 review of a book about Kissinger that “Inevitably, if your ambition is not limited to scholarship but extends to the political sphere, you have to trim your sails to the prevailing winds.”

Hardly Soul Mates

Gewen’s effort to connect Kissinger and Morgenthau is less strained than his effort to link him to Strauss and Arendt. Kissinger took a class with Morgenthau when he was visiting professor at Harvard. Also, for much of the Cold War, they were colleagues as international relations scholars committed to engaging the big policy issues. 

But he overstates the closeness of their relationship. He gives too much credence to Kissinger’s claim that he and Morgenthau “shared identical premises.” His conclusion that “the two German-Jewish realists spoke the same language…it was as if Morgenthau and Kissinger were talking to each other alone, speaking the language of cold-blooded realism and relegating everyone else to the sidelines as naïve kibitzers” seems stretched. 

In trying to make Kissinger and Morgenthau intellectual soul-mates, Gewen plays down profound differences in their contributions to realism as a school of thought and their divergent approaches to America’s role in the world. As Gewen notes, Morgenthau was the “founding father” of modern realism. Despite his lofty profile, Kissinger had hardly any impact on the development of realist thought. He never produced an important theoretical article or book on international relations, and thus his writings are rarely included in syllabi at major universities.

Unsurprisingly, Morgenthau doubted that Kissinger ever aspired to be a theorist, hardly concealing his view that his former student was instead a careerist. As he wrote in 1977, “Kissinger has done, during his adult life, very little that was not oriented toward a particular aim in terms of his personal purpose and particularly his personal power. And he has been eminently successful.” The biggest difference between Morgenthau and Kissinger was that the former aimed to be an intellectual leader who embraced realism because it best described and explained the role of power in world politics. Kissinger’s was episodic and inconsistent precisely because it was not always compatible with his quest for personal power. 

An Inconsistent Realist

Gewen claims—unconvincingly in my view—that Kissinger “always acted out of ‘deeply rooted convictions’ as well as a coherent body of doctrine.” In a 1974 essay in Encounter, Morgenthau sought to distill the essence of the Kissinger “doctrine” to four propositions: first, avoid nuclear war. This was, and remains, a sensible goal, but it tells us little because there are many ways a country might do this from developing a splendid first-strike capability to preempting a nuclear war through deterrence with mutual assured destruction (MAD) to complete nuclear disarmament.

Second, be attentive to the balance of power, a necessary, but by no means sufficient, condition for being a realist.

Third, learn to know and consider the vital interests of other nations, excellent advice that Kissinger gave others but rarely observed himself.

Finally, and in the clearest departure from realism, Kissinger advocated managing international politics through “intertwine[ing]” the interests of great powers so that the “preservation of a peaceful status quo appears to all concerned more advantageous than the benefits to be expected from a unilateral pursuit of antagonistic interests.” This is not realism but rather classic economic and institutional liberalism.

To be sure, Kissinger has consistently maintained that power was important in relations among states and that it should be used to advance the national interest. However, there is a subtle but important difference between a machtpolitiker like Kissinger (and many contemporary neoconservatives), who thinks the world is a nasty place and so accumulating as much power as you can and using it as often as possible is the acme of statecraft, and a realpolitiker like Morgenthau who endeavors to determine when and how power matters and strives to apply those lessons in a state’s interest. To say that power matters and that the world is a nasty place, however accurate, is mere description. More challenging but also more useful is a theory that tells us when and under what conditions power matters in explaining why the world is as it is and provides a guide for statesmen to use (or refrain from using) to advance a national interest. 

A puzzle that Gewen notes but never solves is that Kissinger actually had little influence in the thoroughly realist George H.W. Bush administration but that “probably no administration since Gerald Ford’s drew more heavily on Kissinger’s expertise than that of the second Bush.” Of course, that administration was not realist at all, instead dominated by machtpolitikers like Vice President Dick Cheney and Secretary of Defense Donald Rumsfeld and neoconservatives like Paul Wolfowitz.

In the Obama years, Kissinger made common cause with liberal hawks like Secretary of State Hillary Clinton and United Nations Ambassador Samantha Power. That he consorted with so many non- or even anti-realists is only a puzzle if we regard him as a consistent realist. Once again, Morgenthau saw through him, noting that rather than having a clear and consistent foreign policy doctrine he was “like a good actor who does not play the role of Hamlet today, or Caesar tomorrow, but who is Hamlet today and Caesar tomorrow.”

Realism after Morgenthau

Long after Morgenthau, realism remains a vibrant approach to international politics. His many heirs publish scholarly books and articles that address pressing policy concerns and sign realist-informed policy statements in The New York Times and The Economist. Among the most influential realists are the late Berkeley professor Kenneth Waltz, his students Barry Posen of MIT and Stephen Walt at Harvard, and his successor at the University of Chicago, John Mearsheimer.

Like Morgenthau, today’s realists continue to apply theory to practice. They recognize the limits of power, even when states wield overwhelming military force against their rivals. They are also students of the Prussian military theorist Carl Maria von Clausewitz, who famously argued in his classic On War that despite the pronounced tendency of military force to escalate to all-out war, it should always be regulated in practice by the political objectives that force is supposed to serve. 

The preferred policy for most realists is one of strategic restraint, a policy that would limit states to focusing exclusively on their “vital national interests” when contemplating using military force. Continuing in the tradition of Cold War realists such as George Kennan and Walter Lippmann, today’s restrainers prioritize those areas of the world that directly affect the balance of power. They eschew defining interests in terms of reputation (or credibility), ideology, or the promotion or protection of world order principles, which invariably requires large and sustained military commitments. As the historian Marc Trachtenberg explains, “the power-political approach… provides a kind of yardstick for its judgments about how power might be used intelligently—and above all, for judgments about when its use is to be avoided. In this sense… it is by and large a source of restraint.”

The most pressing post-Cold War challenge thus far has been to ensure that the United States does not overreach as it did in Vietnam and after the Cold War in expanding NATO, intervening in the Balkans, nation-building in Afghanistan, toppling dictators in Iraq and Libya, and chasing Iranian mullahs around the Middle East. 

Kissinger vs. Realism

The best evidence of Kissinger’s occasional realism is how often he stands across the intellectual barricades on major policy issues from realists, past and present. Despite having written a book on nuclear weapons and foreign policy in the 1950s, for example, Kissinger later joined other former policymakers George Schultz, William Perry, and Sam Nunn in advocating complete nuclear disarmament. Most realists such as Waltz and Mearsheimer disagreed, arguing that MAD had kept the peace during the Cold War. Their proliferation optimism even led them to countenance the spread of nuclear weapons to trouble spots in the post-Cold War world such as the former Soviet Union and the Persian Gulf.

On Vietnam, Kissinger also aligned himself against the majority of realists in and out of government including Kennan, Lippmann, Kenneth Waltz, and especially Morgenthau. Indeed, his relationship with the latter was forever altered due to their differences about the war. Kissinger appears to have had private doubts early on, but he recognized that preserving his political viability required going with the Kennedy-Johnson consensus for escalation.

Gewen notes that by 1969 cutting U.S. losses in Vietnam would have been the logical realpolitik move, but Kissinger resisted it as dishonorable. He did everything he could to slow-walk the U.S. withdrawal in the interest of achieving “peace with honor.” He also embraced the credibility rationale for staying the course, insisting that if the U.S. withdrew without leaving an independent South Vietnam, allies would lose faith in our reliability and enemies would be emboldened. Kissinger remained convinced that except for the Watergate scandal, he could have succeeded in preventing the fall of South Vietnam.

While Kissinger publicly supported the war to preserve his political viability, Morgenthau early and vigorously opposed the growing U.S. commitment. He questioned whether South Vietnam’s political problems, especially rampant corruption, could be solved even with overwhelming U.S. military force. He doubted that the “loss” of Vietnam would tilt the global balance of power against the Free World. Finally, in his view, U.S. leaders had the credibility issue backward: the rest of the world had come to doubt our sanity for fighting a losing war in a place of so little strategic importance. 

Gewen makes much of the Nazi rise to power and the subsequent Holocaust in shaping Kissinger’s world view. How much these events really affected his thinking about Vietnam (or any other issue) remains unclear, but they had less relevance for the German Jewish refugee on the other side of the debate. As Morgenthau put it, “Mao Zedong is not Hitler [and] the position of China in Asia is not like that of Nazi Germany in Europe.” 

In a damning comparison, Gewen admits that “Kissinger’s true position on Vietnam before he entered government in 1969 was too complicated, or too slippery, to be summed up by the straightforward words like ‘support’ or ‘oppose.’ He said one thing in public, another in private, and different things to different people. There is no denying his multifaceted opportunism. By 1968, everyone knew where Morgenthau stood on the war. The same couldn’t be said about Kissinger.” 

Gewen begins The Inevitability of Tragedy with an account of Kissinger’s role in the overthrow of Chilean president Salvador Allende. Perhaps no Nixon administration policy outside of Vietnam has done more to blacken Kissinger’s reputation given that Allende was democratically elected and that the military regime that replaced him committed serious human rights violations. In Gewen’s account, this controversy is largely political, with most of Kissinger’s critics attacking him from the left. But in framing it as a left-right issue, he ignores the opposition of moderates who argued on solid realist grounds that despite Allende’s socialism and pro-Castro fulminations, his regime posed little threat to U.S. security. 

To be sure, Kissinger and most realists found common cause on other Cold War policies, including détente, nuclear arms control, and especially the opening to China. These realpolitik masterstrokes have solidified his image in many people’s minds as the Bismarck of the 20th century. But even his Beijing coup d’main did not keep him on the realist reservation for long.

Kissinger’s realist apostasy became most evident with the end of the Cold War, initially in Europe. Most realists doubted that the United States needed to involve itself in the ugly breakup of the former Yugoslavia. Kissinger himself would opine in the Los Angeles Times in 1993 that the United States had “only” two interests in Bosnia: protecting lives and containing the war. Given those quite capacious interests, one wonders what meaningful limits on U.S. interests he would admit there.

He also split from realists on NATO expansion. Given his praise for Castlereagh and Metternich’s efforts at the end of the Napoleonic Wars to reintegrate defeated France into the European system, the last thing he should have advocated after the collapse of the Soviet Union was the expansion of NATO and the exclusion of Russia from it, as he did in a 1994 piece. 

In the early spring of 2003, the second Bush administration took the United States to war against Iraq on the specious ground that the admittedly odious Saddam Hussein regime possessed weapons of mass destruction and was pursuing nuclear weapons. Kissinger was among the cheerleaders for war, along with the neoconservatives and liberal hawks in the Democratic establishment such as Senator Hillary Clinton. The realists, on the other hand, took out an ad on the opinion page of the New York Times arguing that “War with Iraq is Not in America’s Interest.” 

He also aligned himself with the most hawkish voices in the American security community in criticizing the Obama administration’s Joint Comprehensive Plan of Action to rein in the Iranian nuclear program. Unsurprisingly, he supported withdrawing from that agreement. Most realists, however, backed the agreement and took out another ad in The New York Times making their support clear.

Finally, the rise of China is widely recognized as one of the most important geopolitical developments of the 21st century. Kissinger’s response nicely illustrates the chasm between him and the realist community. Most realists believe that the rise of China constitutes the primary strategic challenge facing the United States, although they disagree about how intense the competition is likely to be. 

In contrast to this realist pessimism, Kissinger remains optimistic that the disruptive features of China’s rise can be mitigated by integrating the Middle Kingdom into the liberal world order through socializing it into a “Pacific Community.” Setting aside whether Kissinger’s optimism seems justified (things do not look good at present), it is hardly compatible with realism’s generally pessimistic view of world politics.

In sum, Kissinger turns out to have been at best an inconsistent realist. As a result, he supported two of America’s greatest foreign policy disasters—Vietnam and Iraq—in opposition to most of the most prominent realists of the time.


There are many good reasons for thinking that realism provides the most useful conceptual framework for understanding the chaotic world of the 21st century and that realpolitik offers America the best template for operating in that dangerous environment. But Gewen would have made a much stronger case for the continuing relevance of realism had he written primarily about Hans Morgenthau and relegated Henry Kissinger to a single chapter.

I can only speculate why he chose instead to focus on Kissinger as the avatar of realism, but let me suggest one possibility: his anxiety that, guided by mainstream realism, the United States might slide back into its pre-World War II isolationism. Perhaps the “sorry” Weimar experience that he projects on Strauss, Arendt, Morgenthau, and Kissinger preoccupies Gewen as well. Given that anxiety, a Kissingerian “realism” would be much less of a departure from the establishment consensus of assertive American hegemony of the last quarter century.

Conversely, if realism as Morgenthau and today’s realists envision it actually animated U.S. foreign policy, it would depart significantly from the establishment consensus that has guided that policy over the past quarter century. That realist alternative would not result in a new isolationism. Rather, by limiting American military engagement to defending truly vital interests, a more restrained foreign policy would avoid the strategic debacles that resulted from the overreach that was an inevitable result of the foreign policy establishment’s failure to prioritize and instead intervene in every nook and cranny of the planet. 

Michael C. Desch is Packey J. Dee Professor of International Affairs and Briand and Jeannelle Brady Director of the Notre Dame International Security Center.