To maintain the nation’s self-image as a uniquely humane power that cared about and acted to minimize civilian casualties, yet at the same time developed and deployed the world’s most destructively cruel weapons, U.S. leaders, as Conway-Lanz shows, brought into play two other linguistic devices: “elastic definitions of military targets” in enemy countries, and an emphasis on intention and premeditation that concealed the truth about how the Pentagon actually waged war. When the U.S. military loosed its air power on Japanese, Korean, Vietnamese, Afghan or Iraqi cities, towns, and villages; when it dropped “conventional” bombs and napalm, fired artillery, or used anti-personnel weapons such as cluster and phosphorous bombs that necessarily harmed civilians, it did not do so with the wicked intention to direct those weapons against them or against non-military objects. It did not knowingly commit war crimes, violate international law, or put civilians at risk. But if civilians not directly participating in fighting died, well, that was unintended “collateral damage,” the outcome of a righteous action, dictated by special conditions on the battlefield, not uncontrollable American firepower in the hands of gung-ho pilots or trigger-happy, war-stressed soldiers.
Image-conscious American political and military leaders quickly stepped in to fine tune the official government line. The generals claimed, disingenuously, that when the planes of the US Army Air Force burned down Tokyo and sixty-five other Japanese cities, they had aimed to achieve the goal of accuracy by “alternate means” so as to protect civilian lives while breaking Japanese morale.  As for Hiroshima and Nagasaki, Truman initially “attempted to minimize the impression that civilians had been attacked with the atomic bomb.” His first press release had identified Hiroshima as “an important Japanese military base,” ignoring that the bomb had targeted the city’s civilian center in order to maximize civilian casualties. In his radio broadcast a few days later, on August 9, 1945, Truman re-emphasized “that the first atomic bomb was dropped on Hiroshima, a military base. That was because we wished in this first attack to avoid, in so far as possible, the killing of civilians.”  American newspaper journalists and magazine writers dutifully amplified Truman’s blatant lie by passing quickly over the details and writing their stories “in terms that ignored or obscured civilian deaths.”  Photographic images reinforced this impression: the mushroom cloud, not ruined cityscapes and corpses, told the official story.
Long before Secretary of War Henry Stimson’s article in Harper’s Magazine (February 1947) attempted to stifle further criticism from scientific leaders and ordinary citizens of Truman’s first use, without warning, of atomic bombs, U.S. officials introduced the counter-argument that the bombs had saved the lives of large numbers of Americans who had been scheduled to invade the Japanese home islands. Precisely by adding the saved-U.S.-combatant-lives-argument to Truman’s claim of having respected the norm of “non-combatant immunity,” American leaders were able to elicit uncritical public support for the atomic bomb project and to avoid public debate over terror bombingHerbert P. Bix/Japan focus
The key element was the intention. The proclaimed intention made the result--the killing of noncombatants—tolerable to the American conscience. What counted was the motive, not the consequences of the act or the nature of the weapons used. This extraordinary emphasis on intent in U.S. public discourse on warfare had its roots in both Christian notions of evil and sin as well as U.S. and international criminal law.  Collateral damage is a euphemism of World War II and the nuclear age, coined within the Pentagon, to conceal the deliberate killing of civilians. The military invokes this term as a way of exempting the U.S. from moral and legal culpability for such killing.  In short, collateral damage is all about intent, and the avoidance of responsibility for murdering the innocent. It is the military’s way of saying: judge the commander, the pilot, the combat soldier, even the U.S. mercenary and torturer not by what he did but by his subjective state of mind when he did it.
For over sixty-one years American leaders, firm in the belief of their moral superiority to others, have sought to avoid moral judgments on their conduct of warfare and its close link to war atrocities. Their aim has been to preserve the myth of American good intentions by highlighting the primacy of humanitarian sentiments in restraining the use of violence. Whether in times of peace or war, they propagate the myth of good-intentions in order to reinforce the larger myth of American exceptionalism. The latter is the view of the United States as the embodiment of Western virtue, the deliverer of ‘freedom” to oppressed peoples, God’s model of the world’s future—in brief, a chosen nation with an inherent right to lead others and set the world aright by waging war for the global good.  But since World War II, modern warfare has been more destructive of civilian than of combatant soldiers’ lives; while determining who is the enemy has grown impossibly difficult.
On the Japanese home islands alone, in the savage last months of the war, U.S. conventional bombs and nuclear bombs incinerated an estimated 600,000 to 900,000 noncombatants. Japanese civilians killed overseas bring that total to well over one million. The initial response of the American people and their leaders was to turn away from war crimes, and to avoid public debate about conventional bombing and the human consequences of the uranium bomb dropped on Hiroshima and the plutonium weapon exploded over Nagasaki.