Just after World War II, there were Americans who were astute students of the nature and consequences of American power. America's midcentury leaders — politicians like F.D.R. and Harry Truman, as well as public intellectuals like Reinhold Niebuhr and James Burnham — had seen American might liberate death camps. They had also seen Americans commit wartime atrocities that surpass those at Abu Ghraib.

These midcentury leaders were idealists, but they were rugged idealists, because they combined a cold-eyed view of reality with a warm self-confidence in their ability to do history-changing good.

They took a tragically ironic view of their situation. They understood that we can't defeat ruthless enemies without wielding power. But we can't wield power without sometimes being corrupted by it. Therefore, we can't do good without losing our innocence.

History had assigned them a dirty job: taking morally hazardous action. They did not try to escape, but they did not expect sainthood.
David Brooks