Stephen M. Walt is the Robert and Renée Belfer professor of international relations at Harvard University.

How to explain — and, if possible, predict — a great power’s foreign policy is a perennial question for scholars of international politics. Although a lot of scholarly writing in international relations focuses on the broader system of states (bipolar, multipolar, open, closed, norm-driven, ideologically divided, etc.), we are also interested in why Country X tends to act in one way while Country Y acts differently.

For realists, for example, a key difference is relative power. Realists tend to see all great powers as mostly alike, in the sense that all are constrained by the effects of anarchy, and what makes one great power behave differently from another is its power relative to others. Rising states tend to define their interests more expansively as their power increases, and big shifts in the balance of power typically create windows of opportunity and sometimes increase incentives for preventive war. For others (including a few realists), geography is a key determinant of a state’s foreign policy. One sees this approach in John Mearsheimer’s distinction between “offshore balancers” (Great Britain, the United States) and land powers (e.g., Germany or Russia). Geography can also drive a nation’s desire for “defensible borders” or spheres of influence and affect the ease or difficulty of achieving that goal.

Another obvious way to explain a nation’s foreign policy is by regime type. Democratic peace theory posits that liberal democracies act differently than authoritarian states do, at least in the sense that they don’t fight each other. And there are lots of other theories linking different aspects of domestic politics to foreign-policy behavior, including the differences between parliamentary and presidential systems, the impact of interest groups or “selectorates,” and the long-running debate over whether dictatorships are more or less aggressive than their counterparts.

Lastly, we can also focus on individual leaders. It makes a difference when someone like Napoleon Bonaparte or Adolf Hitler or Lee Kuan Yew or Mao Zedong takes over a country, and sometimes the effects of a particular leader can override those other factors. Speaking hypothetically, if a great and powerful democracy were to elect an unqualified, ignorant, vain, and insecure narcissist as its chief executive, we might expect this decision to have deleterious effects on that country’s foreign policy and international standing. Not like something like this could ever happen, of course.

These are all valid ways of thinking about foreign policy, but I want to focus on yet another way to understand why states act as they do. It is a more historical approach and centers on the impact of great wars. To give credit where it is due, my thinking on this topic has been influenced by two recent works: Austin Long’s excellent book The Soul of Armies and Ariane Tabatabai and Annie Tracy Samuel’s International Security article, published this summer, on “What the Iran-Iraq War Tells Us About the Future of the Iran Nuclear Deal.”

Each of these works argues that major wars have powerful and long-lasting effects on a nation’s subsequent foreign or military policy. In Long’s case, he argues that a country’s first major war tends to shape how it thinks about military organization and doctrine for decades afterward and that the lessons of that initial war experience end up being transmitted and reproduced through the entire military training system. For their part, Tabatabai and Samuel show how the Iran-Iraq War had a profound and enduring effect on how Iran’s ruling elites perceive the outside world and how they think about different foreign-policy tools, including their approach to nuclear weapons. In each case, a particular war turns out to be a seminal event from which much subsequent behavior follows, independent of the country’s relative power, regime type, or the character of particular leaders.

When you think about it, these insights make perfect sense. Great wars are wrenching, costly, and frightening events that affect all of society; they are episodes where the future of the entire country is on the line. Those who fight in these wars are often scarred by the experience, and the lessons drawn from victory or defeat will be etched deeply into the nation’s collective memory. The experience of past wars is central to most national identities, and national security remains one of the paramount justifications for having a strong state apparatus. The narratives that states construct about great wars help define what it means to be a patriot, or a “good citizen,” and help set the boundaries for political discourse for years to come.

If you want to understand the foreign policy of a great power, therefore (and probably lesser powers as well), a good place to start is to look at the great wars it has fought. And for most of the major powers, the last great war is still World War II. If one asks what this perspective to some contemporary powers, what might it reveal?

Winston Churchill called World War I and II the “Thirty Years’ War of the 20th Century.” Not surprisingly, these two conflicts have shaped Britain’s views on foreign and military policy ever since. As the interwar writings of B.H. Liddell Hart reveal, the carnage of World War I made the British leery of a future “continental commitment” and encouraged the policy of appeasement. After World War II bankrupted the empire, British leaders concluded that the key to future influence was nurturing a “special relationship” with the American colossus. That lesson has remained pretty much intact to this day. Geography, relative power, and ideological affinities no doubt play a role here, but these two great wars are what drove that lesson home.

For Germany and Japan, the impact of World War II was very different but no less profound. The war ended disastrously for both — Germany was split in two, and Japan was firebombed and had two atomic bombs dropped on cities — and each learned that unchecked militarism and/or fascism was a recipe for disaster. Not surprisingly, each has been among the most pacifist countries on the planet ever since, even in the face of challenging security environments. Even if these tendencies eventually fade (as they may now be doing in Japan), it is clear that the historical experience of that great war had a major impact on both states’ foreign and defense policy for the past 70-plus years.

For Russia, the “Great Patriotic War” was also an unmitigated disaster, exacting a price of more than 20 million people dead, along with thousands of ruined cities, towns, and villages. Not surprisingly, the experience strongly reinforced Russian leaders’ sensitivities about borders, their desire for a sphere of influence in the “near-abroad,” their tendency to assume the worst about others’ intentions, and their willingness to sacrifice creature comforts for the sake of security. If you don’t understand what World War II was like for the Soviet Union, and how that experience is still central to Russia’s worldview today, you’ll miss a lot of what is driving Moscow’s current behavior.

China’s situation is more complicated in my view. I’d argue that World War II is not the dominant historical event shaping China’s behavior today. The brutality of the war helps explain China’s enduring suspicions of Japan, but the more important historical experience is the two prior centuries of humiliation China suffered at the ends of the West and then Japan. Today, the belief that China has now regained its “rightful” place among the major powers is a powerful source of legitimacy for China’s leadership and motivating force for its population.

And what about the United States? For Americans, World War II is still the “good war,” a heroic episode that has informed and guided the nation’s thinking about itself and its role in the world since 1945. It taught several generations of Americans about the hazards of appeasement, the (alleged) importance of credibility, the dangers of isolationism, the value of allies, and the need for military supremacy. And because Americans convinced themselves that they were primarily responsible for the Allied victory (a view that conveniently ignores the far greater role played by the Soviet Union in defeating Germany), the “lessons” of World War II reinforced the notion that America was the “indispensable” power that must lead everywhere.

One could argue that the Cold War had an equally profound impact — especially in the immediate aftermath of the Soviet collapse — but the effects do not appear to have been as lasting. True, America’s Cold War triumph ushered in a period of heady optimism and led Americans to think that liberal democracy was the wave of the future just about everywhere, but that naive vision crashed and burned in the sands of the Middle East and the mountains of Afghanistan. None of America’s Cold War conflicts went especially well, and one of them — Vietnam — was a disaster. The Cold War was ultimately won not on a battlefield but in the marketplace and at the negotiating table, and there’s really no great martial lesson or moment of George Patton-like panache in that long struggle. The West triumphed because its economic model was superior — which allowed its citizens to amass sufficient power to protect themselves and live pretty well while doing so — and because the United States was much better at recruiting wealthy and powerful allies than the Soviet Union was.

Moreover, the lessons of Vietnam — and especially the futility of nation-building in poor and divided societies that we do no understand — were forgotten with remarkable speed. Nor do I expect Iraq or Afghanistan to exert as profound an impact on American consciousness, because a relatively small percentage of Americans fought in those wars, those who did were mostly volunteers, and the costs of the war will be borne by generations who have yet to be born.

But one cannot help but wonder if the lessons of World War II are bound to fade as well. The “Greatest Generation” is nearly gone, and watching Patton, Fury, Saving Private Ryan, or, god forbid, Inglourious Basterds is no substitute for living through the real thing. Memorials, books, and other cultural constructs can keep these narratives alive for a long time, but they are always vulnerable to new events.

And here’s a kicker: The next profound shaping event may not even be a war. The danger of war is ever present (even today), but perhaps some combination of nuclear deterrence, economic interdependence, good judgment, dumb luck, and careful diplomacy will prevent another great-power war for another 70 years or so. If that is the case — and I hope it is — and if the long shadow of World War II eventually dissipates, then it might be some other vast collective event that shapes our perceptions of danger and our definitions of heroism, sacrifice, and even identity. If events like Hurricane Harvey become the norm rather than the exception, maybe coping with recurring natural disasters will become how states and societies define themselves and their heroes.

None of the above implies that relative power, geography, regime type, or leadership is irrelevant to understanding a state’s foreign policy. But the wise analyst will remember that social memories of big collective experiences — like wars, depressions, plagues, revolutions, etc. — inevitably have strong and lingering effects on how those other qualities operate. Or as William Faulkner famously put it, “The past is never dead. It’s not even past.”

Πηγή: Foreign Policy