ROBERT SIEGEL, HOST:
After his speech, President Trump visited the graves of fallen service members who died in Iraq and Afghanistan, walking among the white marble headstones. On a day when we remember those who died fighting in America's wars, we're going to take a moment to ask, how many casualties of war throughout the ages died unnecessarily? And I don't mean in friendly-fire incidents or moments of tactical error, I mean in wars that could have been prevented.
The Harvard political scientist Graham Allison says that many conflicts were unnecessary. Allison has written about conflict starting in ancient Greece - conflicts in which an established power has felt threatened by a rising power. And he's written a book called "Destined For War: Can America And China Escape Thucydides's trap? Graham Allison, welcome to the program.
GRAHAM ALLISON: Thank you very much for having me.
SIEGEL: Thucydides was an ancient Greek historian. What was the trap that he described?
ALLISON: The trap that he described goes, when a rising power threatens to displace a ruling power, one sees inherent structural stress that makes conflict likely. I look at the last 500 years, find 16 cases - 12 of them ended tragically in war, four in not war. And I hope that we can learn the lessons of the past in looking at the current challenge that China poses to a ruling America.
SIEGEL: Is the rise of China creating a fear in the United States that might, indeed, lead toward a war?
ALLISON: I think absolutely. And I think the election of Trump was an expression of what happens in ruling powers as they become alarmed. So the big question in the book is what the impact of a rising China will be on the U.S. and on the international order that the U.S. has organized for the past seven decades.
SIEGEL: What are the keys to averting a conflict?
ALLISON: Well, in the cases in which war was averted, both the rising power and the ruling power had to make painful adjustments. And in both cases, one when needed surges of strategic imagination that would do something more than business as usual.
SIEGEL: Another reading might be that the age of nuclear weapons has made the kind of conflict you describe less likely to turn into a war and that that's why the Cold War stayed cold, for example. Could mutual deterrence prevent a U.S.-China war down the road?
ALLISON: Absolutely. One of the three big factors that count against war in the relationship between China and the U.S. are, first, nuclear weapons and even a condition of mutual assured destruction. Secondly, one's got two economies that have become so deeply interlaced that a war between the U.S. and China would leave Wal-Marts empty and Chinese factories producing for nothing. Thirdly, climate - if between the two of us, we keep doing what we're doing, we can create a climate in which our grandchildren won't be able to live.
SIEGEL: As presidents have done before him, Donald Trump went to Arlington National Cemetery today. This, of course, was once a land owned by Robert E. Lee that was taken, and Union soldiers were buried there after the Civil War. There are people interred there who fought in both world wars and other conflicts.
I can understand very easily the argument that the first World War was somehow avoidable, that it was a conflict of mistakes and misjudgments. World War II or for that matter - you don't write about much the Civil War. Were they really unnecessary, avoidable wars?
ALLISON: Well, I believe that we've - the Americans have had more unnecessary wars than necessary wars. World War II, though, as you say, is the hard case. If the Britain and France had done what they were obliged to do under the treaty and sent troops to enforce the treaty when Hitler remilitarized the Rhineland, the German general staff would have turned Hitler out. And one would not have had a cause for war, and you wouldn't have had World War II.
SIEGEL: Of course, considering that by the time that Germany and Russia had carved up Poland, and Germany later attacked the Soviet Union, the U.S. didn't have those choices anymore. The U.S. couldn't turn the movie back to 1933. So U.S. entry in that sense could be called necessary in an unnecessary war.
ALLISON: But there was nothing preventing the U.S. being an actor in 1933 except for the fact that we had - basically, the Senate had rejected the U.S. role in the League of Nations. I mean, if Woodrow Wilson's vision had been the case and we'd stayed involved in Europe in the period in between, then we and the Brits and the French could have prevented Hitler becoming what became World War II. But by the time we sat on the sideline, it was too late, as you say.
SIEGEL: Graham Allison is director of the Harvard Kennedy School's Belfer Center for Science and International Affairs. And he's the author most recently of "Destined For War: Can America And China Escape Thucydides's Trap?" Thanks for talking with us today.
ALLISON: Thank you very much for having me. [POST-BROADCAST CORRECTION: We incorrectly say that Arlington National Cemetery is on land once owned by Robert E. Lee. According to the cemetery, the land was owned by the family of Lee's wife; Lee was custodian but never owned it. ]
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