It's our fault...

Let's agree for the sake of argument that America has helped to bring about or sustain a great deal of evil in the world. We were once an ally of Saddam's Iraq, aiding it in its war against Iran. We armed Islamic guerillas in parts of Asia. We supported despots in Africa. Let's just agree that we did these things, which had terrible consequences, and we were wrong in doing them.

What follows from this? Critics of American foreign policy can be inconsistent on this matter. Sometimes, it follows from the fact that we had a hand in the rise of a particular evil that we have no right to oppose it. I've heard this kind of reasoning many times in connection with Saddam Hussein. Sometimes, it follows from claims about our dirty hands that we ought to rectify what we helped to bring about. I've heard this reasoning many times in connection with African genocide and other matters. Again, I'm not disputing any factual claim here. I just can't see how judgments about responsibility for bad things can have such wildly varying implications. Does it depend on who is the target of our action?

Many parties appear to be very selective in how they apply these lines of reasoning. It only seems to come down to this: when you support a certain course of action, our responsibility for the status quo only counts as a reason in favor of action; when you oppose a certain course of action, our responsibility for the status quo only counts as a reason against action.