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History’s Largest Lessons

June 2024
18min read

A historian of the ancient world believes that in every era humankind has reacted to the demands of waging war in surprisingly similar ways, and that to protect our national interests today Americans must understand the choices soldiers and statesmen made hundreds and even thousands of years ago

In a time when the usefulness of the past as a means to comprehend the present remains the object of skepticism, if not outright attack, inside the academy, Donald Kagan, the former dean of Yale College and a professor of ancient history, has published a book about the necessity of historical analogy for understanding a nation’s security interests.


In a time when the usefulness of the past as a means to comprehend the present remains the object of skepticism, if not outright attack, inside the academy, Donald Kagan, the former dean of Yale College and a professor of ancient history, has published a book about the necessity of historical analogy for understanding a nation’s security interests. The most common arguments against such a view hold that modernity is so profoundly different from all previous human experience, and the past so particular and irreproducible, that analogies are necessarily anachronistic misreadings and can only mislead us.

But Professor Kagan believes that if we are to understand the world in which we live, we have no surer source, indeed no other source, than the past. Whatever the flaws, whatever the difficulty, there is simply nothing better available.

Professor Kagan is perhaps best known as an expert on the Peloponnesian War, waged from 431 to 404 B.C. His recent book, On the Origins of Wars , argues that close study of fifth-century Greece and second-century Rome remains the best way to understand the catastrophes that made our century and to ward off similar ones in the next. This argument flouts a number of his colleagues’ certainties: that professional specialization puts the twentieth century offlimits to him and that the distant past is unsuitable terrain for comparison to modernity. On the Origins of Wars makes bold claims to the contrary, and I went up to New Haven to hear Professor Kagan defend them.

Why do you believe so strongly that despite current academic convictions to the contrary, history is essential for modern statesmen, and for the rest of us too?

There’s no escaping history. No matter what people say theoretically, in their daily lives they take note of the past and make judgments about the likelihood of its recurrence. The drunk husband coming home at 2:00 A.M. knows from past experience to be very, very quiet. That is the study of history in its most simple sense, and people couldn’t live from day to day without doing a fair amount of it, which reveals something about history in the larger sense: Everybody knows perfectly well that there are constants in human behavior as well as discontinuities, and if this weren’t true, our capacity to function in the world would disappear entirely.

We tend to focus on economic interests as the source of conflict.… But the hard evidence belies this.

You begin the book with an analysis of the outbreak of the Peloponnesian War, follow it with a chapter on the origins of the First World War, then compare the causes of the Second Punic War and World War II. This implies that historical analogies are least prone to obsolescence where the stakes are as high as they can be: in war.

Right. It’s in the realm of international relations, diplomacy, and war that the constancies are much greater than they are in other areas. One of the things that the book means to do is to reveal that by taking the reader into the council rooms of the people making the decisions. I’m struck by how much similarity there is about the nature of the problems, the rather limited range of options available in these circumstances, and the motives that people have in choosing one rather than the other; these have remained amazingly constant, even in a nuclear age. The greatest difference between ancients and moderns, which lies in the economic reorganization of life wrought by the Agricultural and Industrial Revolutions, has not fundamentally reordered the logic of international politics.

Bernard Brodie, the master of strategic thought in the age of nuclear weapons, made one of the strongest objections to your thesis half a century ago when he argued that all past lessons about the logic of war had to yield to the fact that fission bombs made war between nuclear powers fundamentally irrational.

It seems to me that there have been a number of occasions when war ought to have been unthinkable, because the disparities of power were tremendous and the capacity of one side to obliterate the other ought to have been obvious to all, but that did not prevent the players from confronting one another.

Probably the most famous case is the one that Thucydides described in what is called the Melian Dialogue during the Peloponnesian War, when the Melians were made perfectly aware that if they didn’t do what the Athenians wanted, the Athenians would obliterate them. People seem to think that only nuclear weapons can thoroughly destroy a civilization, but when the Athenians got through with Melos, they killed all the men and sold all the women and children into slavery. I regard that as sufficiently horrendous an outcome that to speak of worse is pointless. So this kind of issue has existed before.

You take up Thucydides’ point that men go to war for three fundamental reasons: out of honor, fear, and interest. But doesn’t honor seem an archaic motive?

I think one distortion in our current thinking, largely created by Karl Marx, has dominated Western ideas for well over a century: We tend to focus on economic interests as the source of conflict and interpret politics accordingly. But the hard evidence belies this. When we look at the decisions made by the people who decide on war, it’s fascinating how infrequently economic concerns are on their mind.

Instead, people are motivated by what Thucydides would have called honor, which we are more likely to call questions of prestige. There are few other issues, and I don’t mean just for public consumption; I mean, as these people talk to one another in their own circles. So it’s pretty hard to escape the notion that a very, very old concept is alive and well today.

You argue that the interests of a state depend on its moral credit, the perception by its adversaries that under someconditions it will fight, which means that its prestige has a real deterrent value and so is at the heart of its interest. So how can you separate honor and interest?

What must he understood—and I think Thucydides meant for us to understand this—is that though one can separate them in ways that are helpful and meaningful, honor, fear, and interest all are related to one another. Let me give you an example. If a state finds that its honor is at risk, that it is treated with contempt, the other two elements of the triad immediately become part of the story. Men get fearful that in light of this contempt others will take advantage and damage their real interests.

It’s very important to make the separation, because otherwise it’s easy to slide back into the obsessive materialism of the Marxist analysis. I.enin argued that Kuropeans established and expanded empires to acquire economic benefits alleged to flow from political control. But if you actually look at imperial ventures, you discover that in most cases the F.uropean powers did not get any economic benefits. So what were they up to? They were in competition for glory, eminence, prestige —in other words, honor.

Yet you point out in your book that in the case of World War I the strongest supporters of the single most destabilizing German policy, the naval race, were German businessmen.

Of course, some businessmen benefited from the construction of the German fleet. Elements in society with a direct economic stake in something will obviously tend to pursue their private interests. The question is, Why does the government, which doesn’t share those particular interests, pursue a course that may be economically detrimental to the country at large?

And who started the naval race? It’s clear that the German government encouraged the businessmen and bankers whose imperialist organizations were paid for with government money. And so on. The much-touted Berlin to Baghdad railway had no persuasive economic rationale; the German government had to dragoon the bankers into supporting it. That was typical of what was happening.

What about the quest for power?

Well, this seems obvious to me, but it’s amazing how many people who write about these subjects ignore it. In the end what people really go to war about is power, by which I simply mean the ability to have their will prevail. Nowadays in the United States, and to a degree in Britain and a few other parts of Western F.urope, there is an increasing sense that power is inherently evil, and that seeking to maintain or increase one’s power is a villainous activity. This strikes me as a serious mistake.

Every being and every nation requires power for two purposes. The first is to he able to do what it wishes to and must do, some of which will he good and perfectly natural things. Second, one needs power to keep others from imposing rheir will, to prevent evil things from being done. Only in the Kingdom of Heaven would it be unnecessary for human beings to have power. Power is morally neutral, and throughout history nations of every kind have been concerned with maintaining and increasing their power.

Your theory gives us a way to think about the place of the United States in twentieth-century history and about the outbreak and avoidance of war in our era. Don’t you believe that the great lesson to be drawn from the origins of World War II is that nothing is more dangerous than assuming that a momentary deterioration in a state’s power is permanent?

I suppose you’re referring to the abnormal condition of Hurope after the Hirst World War, when Germany’s power had been temporarily reduced by the conditions of the peace. It was immediately apparent that there were only two possibilities. One was that the victorious nations would simply impose weakness on Germany for as long as they could, which could have been for quite a long time if they’d maintained the will to do it. The other possibility was that Germany would very quickly become once again the most powerful state in Hurope. And of course, that’s what happened.

But the states that declined to impose a long period of weakness on Germany would not face the inevitable consequences of their action. One should never make the common mistake of assuming that what is true today may be projected in a straight line into the future. The natural order of things is change, particularly in the realm of international relations. The belief that refraining from action preserves the prevailing condition is another very common mistake.

But how do you pick the right analogy? For example, one could decide that a collapse of Russian power is always eventually reversed, and so the United States is looking at a momentarily diminished country and should either appease it or protract its powerlessness. But if flux and change are the constant, maybe Russian power is over. Given your theories, how do you determine what you’re looking at?

There is no way to determine from historical analogies what the real danger is at any particular time. And 1 shudder a little at the use of the word theory . I would not like to associate myself with the view of the political scientists who suggest that there are theories of politics that are in some way analogous to theories in the natural sciences because I don’t think that a theory derived from the study of history has direct predictive power. The difficulty in human affairs is to assess the facts at a particular time; at least that’s one of the major difficulties.

So, yes, there are contradictory possibilities. All I’m saying is that history suggests that Russia almost always possesses a minimum quantity of power, that in its current situation it is probably less strong than is natural, and that its power is very likely to increase considerably. However, it’s perfectly possible that this will not happen and that the new arrangement, which seems to me rather fragile, may turn out to be a lasting one, and Russia’s ability to menace its neighbors will be decreased permanently.

Again, how can history help us tell? In 1815 Russia was the most powerful European state. In 1856 it still appeared to be but proved to be the weakest, because of the impact of the Industrial Revolution on military strength. In 1878 it looked pretty formidable again; then after 1905 Russian power seemed to be out of the equation but actually was on the upswing very soon. So how do you determine these things in anything other than the shortest run?

In my view America represents something relatively new in the history of international relations.

I’m sorry, but the best you can do is find out the available facts and then be smart. All that historical knowledge can offer us is a variety of appropriate, or at least plausible, analogies. They may contradict one another, but they give us at least some sense of what possibilities to look for.

In the case of our own near future, which nations might conceivably fit the 1920s and 1930s model of powers that are only momentarily militarily insignificant or weak? Do you consider Japan and China such? For the last two thousand years China has usually been a much stronger power than it has been for the last two hundred.

You left out Germany. In all these cases it is prudent to expect problems sometime down the road because these states have traditionally possessed much more relative military power than they do now. Therefore one should look for the return to such a condition, both because it’s possible, as demonstrated by their past power, and because of the role of honor; formerly powerful states regard great strength as their normal condition and feel dissatisfied with any lessening of their power. And it’s discontent that shakes up the international situation. I think it’s entirely possible that Japan will not again be a military power. But one shouldn’t count on it, because Japan has all the things necessary, for the moment, to be a serious military power if it demonstrates the will. Of course, you can’t tell which way it’s going to go—both are possible—but if one of them is possible, you must not forget it just because right now Japanese political culture disdains military power.

Let’s take the Chinese. They’re still more backward in technological and other ways than Japan and Germany, but their sense of their uniqueness, of their cultural pre-eminence, may be even more powerful. Given my own proclivity for taking these ways of thinking very seriously, the Chinese, should their capacity make it possible, might be the most dangerous of all. Now, if things go badly—a time of troubles, a period of internal conflict, and this is entirely possible—China could be torn so seriously as to take it out of the picture for a long time. But my own judgment is that this is unlikely. There are a well-organized and powerful military and a well-entrenched bureaucracy, both hell-bent on hanging on.

If they do, we’ll be dealing with a China that’s got both strength and prosperity. That kind of China has historically been brusque, arrogant, and aggressive in its dealings with its neighbors, as it is now. The likeliest area of Chinese rambunctiousness is Taiwan. There is a tremendous emotional commitment to resuming control of Taiwan, and we won’t be able to walk away from Taiwan, no matter what we pretend. Another area is South Korea, which is a flourishing and increasingly liberal and democratic society. Again we can’t walk away from it. And last, Japan. China may well attempt to browbeat Japan. The United States could very easily find itself in a confrontation with China over any of these places.

But will China be able to continue economic modernization with the regime in place? Sustained modern economic growth seems to require the rule of law—at least the sanctity of contract—and the evidence suggests that this remains incompatible with communist state power.

I have no answer to that paradox, yet nobody could have predicted the success of the Chinese economy to date. National characteristics make a difference; they survive in all sorts of strange circumstances and may make China richer than any other society ruled by a similar regime. And the wealth necessary for China to be scarily strong is almost within its reach now. China will not need maximum economic efficiency to be a real problem.

What about the Islamic world?

I think imminent conflict with the United States has been oversold. History suggests that the prerequisite for a conflict with Islamic civilization is the political unification of at least a large portion of that civilization, and that is not very likely; it didn’t last very long even at the very beginning. The long Ottoman threat to Europe was a Turkish threat, not a pan-Islamic threat. Islamic states fight one another vigorously.

If you start with the Mohammedan period, in the seventh century, you notice that Islam broke apart pretty quickly. Islam suffered internal splits, akin to those in Christianity, and thus significant divisions remain. Islam contains many powerful ethnic groups. The Iraq-Iran War was an ethnic war as much as it was anything else. And many Muslims have found advantages in cooperating with the West.

So where does all this leave America?

In my view America represents something relatively new in the history of international relations. We are the greatest military power in the world today and we remain the greatest economic power. There haven’t been very many times in the past when there has been a single power with so much relative strength.

And we are still almost universally perceived to be what Bismarck called a satisfied power, happy with what we have, self-sufficient, not aiming to seize anything essential to others. We don’t represent the kind of menace that powers approaching our relative strength have in the past. So I think there is a new set of rules for us: If America tries to exert leadership in the world, it can do so in ways that are historically new.

But you have also argued that this very exceptionalism may have led us to believe that the rules of the state system have changed more than they really have, which makes isolationism tempting.

Yes, we remain in many respects an insular power, like Great Britain vis-à-vis Europe before the development of the aircraft and the submarine. We still unconsciously rely upon distance from others, and our combination of pre-eminence and contentment means that while we can exercise world leadership with significantly less threat to others, this is offset by the fact that we are all too likely to assume we need not exercise any power at all.

The main lesson I’ve learned from looking at history in general, and the history of the twentieth century in particular, is that the United States, with its tremendous interest in maintaining something like the status quo, must retain its position as a great power in the world, able to help direct the course of events, and not simply count on its current good fortune and retreat into a passive observer’s position. That’s the great thing we can learn from this century. One has to look at the specifics to determine the proper American reaction to any given situation, but if you dissipate your power, you’re not going to have anything to say about what happens.

So you find the increasing embrace of isolationism by both left and right one of the more disturbing features of American politics.

From Vietnam until quite recently it seemed to be a position taken chiefly by the left and the Democratic party. But since the end of the Cold War the Republicans have become at least as prone to embrace a policy of international disengagement. I fear that what formerly prevented this among Republicans was less a recognition of the realities of international politics than a visceral hostility to communism, so that when communism disappeared, they did not understand that America’s interests and security, and the world’s capacity to avoid war, still required close American engagement.

You also believe that Americans retain a large bump of what’s often called Wilsonian moralism, which leads to the vigorous prosecution of a war and then a retreat in disgust from the imperfect world that they’ve necessarily created. Do you think we’re in a phase like that?

Yes. We’ve been challenged this way three times in this century. In World War I we were sold a bill of goods that we were fighting for the principle of democracy, when we were in fact fighting to check a dangerous militarism and preserve the balance of power in Europe. We were very swiftly disillusioned by the results we had won. Then, in the Second World War, a tremendous ugliness appeared in the world in the various forms of fascism and Nazism, and we destroyed them, although another very ugly form of power immediately expanded in their wake. The interesting thing is that we did not withdraw that time; we remained deeply engaged and checked the menace we felt from the Soviet Union.

So the Second World War legitimized the necessity of maintaining an imperfect world—a balance of power stabilized by peacetime American military preparation- for a generation or two, but that was unique in our history. Isn’t the rebirth of isolationism the natural consequence of the aging and death of a generation that knew some harsh things?

Yes, I think that that’s a very large part of it. I also think that there was a delegitimizing of that point of view. That was part of the consequence of the Vietnam War, so that all sorts of people for all sorts of reasons first denounced that war as particularly vicious and wicked, with some going on to generalize from that that the entire waging of the Cold War was illegitimate and wicked. In many quarters that cast a taint on the exercise of military power in almost any fashion, and this was new in America. Prior to the First World War few Americans believed in the illegitimacy of war under all conditions; they understood it to be just and necessary sometimes. The loss of that broad understanding seems to be a new element.

Your book provokes reflection on the misreading of historical analogies. I’m thinking particularly of Henry Kissinger’s pessimism about postwar America.

I’m most troubled by Kissinger’s role in the Nixon administration, first as the national security adviser and then as the Secretary of State, in which his general model was that the United States was a sunset power in its declining phase. Our power was going to contract no matter what happened, and we had to adjust to that. In consequence we were sup- posed to come to terms we might not like with the Soviet Union. It seemed to me then, and of course it now seems to me all the truer, that this was an erroneous evaluation of the relative power situation in the world and of what was likely to happen.

I think Kissinger simply conflated the President’s domestic situation with the country’s situation.

It derived, however, not simply from a mistaken calculation of the facts but from a misidentification of the very real weakness of the regime of which Kissinger was a part as America’s alleged national weakness. The Nixon administration rarely had the power to have its will carried out in the United States, and I think Kissinger simply conflated the President’s domestic situation with the country’s situation, to the great harm of our foreign policy. It was the second Nixon administration that was disintegrating, not America.

Do you think a misreading of history is also responsible for the current conviction on the part of many policymakers that because Americans are so intolerant of realpolitik and limited war, you must have the absolute and unconditional advance consent of the American people before you can use force?

And you must wage war briefly and with such over-whelming force that we can’t possibly lose more than three or four men, and all those other impossible requirements. These people assume that the American tolerance for war is so low as to be effectively zero. I would say they’ve learned yesterday’s lesson and are applying it to the future in a straight line, looking back at the worst situations resulting from Vietnam and ignoring all evidence to the contrary.

It’s very interesting that late in the Bosnian crisis, while all advanced opinion was saying that we couldn’t possibly put troops in there because the American people wouldn’t stand for it, polls showed that anywhere from 61 to 78 percent of the American people favored involvement by American troops in Bosnia—the 78 being for some limited purpose and the 61 being for rather strong involvement. The truth of the matter is that the American people’s capacity to make these judgments depends to a considerable degree on the leadership that is in place. A leader who has a capacity to make the case for military action, even if it doesn’t meet those extraordinary requirements, can bring that action about.

The military is mired in the seventies and has gotten thoroughly out of hand for some time now, imposing what amounts to its political judgment on the civilian government. The military has no business announcing the conditions under which it will contemplate going to war. It’s reminiscent of the behavior in the 1930s of the French and British military leaders, who were consistently making judgments that seem in retrospect to have been shaped by political opinions: in the British case, “We’re not going back onto that damn continent”; in the French, “We’re not taking losses the way we did in the world war.” They always made the worst-case analysis of Allied prospects and the best-case analysis of German ones. I see some small similarities between that and the post-Vietnam political views of our military leadership today.

Everybody is behaving in accordance with his professional interests. I think you have to understand the British generals then and the American generals now in the same way. The common opinion among respectable, educated people sixty years ago was that these generals were stupid or callous and immoral; they had been responsible for a tremendous slaughter. Those generals’ self-esteem and fear of criticism militated toward avoiding that kind of situation.


Similarly, America pilloried its military leaders after the Vietnam War as stupid, dishonest, callous, and brutal. Now their personal and professional self-esteem is tied up in preventing the re-emergence of a similar climate of opinion. Everything is based on that one analysis: Let’s see what happened in Vietnam, and let’s see that nothing like that ever happens again.

Let me make this very clear: I think the hardest thing that human beings have to do is be military leaders. The intellectual problems of deciding how to wage war well are so fantastic that anybody who does it deserves an incredible amount of admiration. So it’s not surprising that many of these people tend to be very cautious people, who spend most of their time thinking about how not to lose—how not to be humiliated, how not to be made to look foolish, and how not to be defeated- rather than about how to win. I don’t mean to say the latter is excluded, but the former predominates.

When you have had anexperience that is almost entirely negative, which the Vietnam War was, you tend to become fixated upon avoiding that kind of mistake. And you may not think enough about the fact that the next thing you’re going to get engaged in very likely won’t be the same.

One of the responses the British made to World War I was an increased call in some quarters for a predominantly maritime strategy. The American military also displayed a similar interest in the wake of Vietnam, although it is not clear that maritime strategies are viable in the face of modern airpower and submarine forces. Do you think the Reagan naval buildup was also part of the Vietnam syndrome?

I think the Navy remains a linchpin of U.S. military power, and we can never get away from that, barring an utterly unforeseen technological revolution. Certainly in our lifetime the Navy is going to be a critical part of any strategy, both military and diplomatic, because wherever we’re going to fight we’re going to have to use ships to deploy forces there. That means we’ve got to protect sea-lanes and all the things that flow from that. So there’s no escape from maintaining our status as the pre-eminent naval power.

It just struck me that instead of talking about how useful historical analogies are, we’ve been discussing how dangerous they can be.

No, we’ve been talking about how dangerous a single analogy can be. There’s a strong human tendency to seize on the most recent analogy that has impressed itself upon one’s mind or an analogy that happens to fit one’s prejudice in advance and tends to support what one wants to do anyway.

The obvious defense against this is to multiply the number of analogies that have some resemblance to the current problem. Best of all is to retain analogies that seem to run counter to one another in the lessons that they teach. That will help you about as much as anything will, because it will compel harder and deeper thought than anything else. I’d paraphrase John Stuart Mill on democracy: Historical knowledge is at best deeply imperfect and dangerous, and the only solution to this problem is to have more and more of it.

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