America's Habit of Revenge

''ALTHOUGH THE WAR did not make any immediate demands on me physically, while it lasted it put a complete stop to my artistic activity because it forced me into an agonizing reappraisal of my fundamental assumptions.'' These words were spoken by Thomas Mann in his Nobel laureate speech in 1929, a reflection of the broad psychological rupture inflicted on the European mind by World War I. But just as war can lead to the ''reappraisal of fundamental assumptions,'' it can do the opposite, reinforcing assumptions to the point of shutting down debate. That seems a more American story.

Tomorrow marks the 58th anniversary of the atomic bombing of Hiroshima. Oceans of ink have been spilled on the questions of whether Harry Truman's decision to use the bomb was justified; whether the Japanese would have surrendered without it; whether the bomb, therefore, was truly an alternative to a bloody invasion; whether the bomb was actually aimed at intimidating the Russians; whether, in fact, given the momentum of war, Truman's decision was really a decision? Such questions never go fully away because each has some claim on the truth, even if only partial. But the ''fundamental assumption'' underlying the bomb's use is rarely addressed.

''Having found the bomb, we have used it.'' These are words spoken by President Truman in a radio address to the American people on the evening of Aug. 9, the day a second bomb fell on Nagasaki. ''We have used it against those who attacked us without warning at Pearl Harbor, against those who have starved and beaten American prisoners of war, against those who have abandoned all pretense of obeying international laws of warfare.''

President Truman, and others who justified the bomb, would rarely speak this way again - a direct articulation of revenge as a main motivation for the overwhelming destruction of the Japanese cities. In his radio remarks, Truman went on to add the other justifications: ''We have used it in order to shorten the agony of war, in order to save the lives of thousands and thousands of young Americans. We shall continue to use it until we completely destroy Japan's power to make war. Only a Japanese surrender will stop us.'' But even the surrender, when it came, would prompt after-the-fact controversy, since, clinging to the emperor, it wasn't unconditional. If we accepted Japan's hedged surrender after the atomic bomb, why wouldn't we accept it before?

Every justification offered for the use of the atomic bomb would be clouded by ambiguity except one - revenge. It was the first justification Truman offered, speaking the primal truth, and it was the only justification the American people needed by then. But soon enough, revenge would disappear from all official explanations, and even Truman's critics would rarely address it except obliquely. Much better to debate the necessity of that invasion.

Americans do not like to acknowledge that a visceral lust for vengeance can be the main force behind national purpose, and that is why the Aug. 6 anniversary always arrives beclouded. In 1995, when the Smithsonian attempted to mount a retrospective exhibit observing the 50th anniversary of Hiroshima and Nagasaki, a mainstream consensus slapped down any effort to ''reappraise the fundamental assumptions'' of the bomb's use. President Clinton declined to second-guess Truman, and the Smithsonian exhibit was canceled. What terrifies Americans is the possibility that stated reasons are distant from, or even unrelated to, the real reasons for the nation's behavior. But Truman had it right the first time: to understand Aug. 6, 1945, you must return to Dec. 7, 1941, the score that had to be settled.

Pearl Harbor resurfaced in the American memory on Sept. 11, 2001. Again and again, the Day of Infamy was invoked as the relevant precedent - the only other time the United States had suffered such a grievous blow. And just as before, there was never any doubt that the blow would be avenged. Moving quickly away from the unsatisfyingly abstract ''war on terrorism'' and then from the frustration of Osama bin Laden's escape in Afghanistan, President Bush took America to war against Iraq to satisfy that primordial need. And it worked. The United States of America clenched its fist the day the twin towers came down. Against Iraq, the United States finally threw a punch that landed. That is all that matters.

The controversy over the Bush administration's misleading ''justifications'' for the war in Iraq is a reprise of the endless debate over ''justifications'' offered for the atomic bomb. Neither set of questions grips the American conscience. There is no ''agonizing reappraisal of fundamental assumptions'' in this country. When we want our revenge, we take it. And, even as the flimsy rationales with which we cloak it are stripped away, we fervently deny that vengeance, not justice, defines our purpose.