If one believes that we are responsible for our ancestors, then I suppose Americans have forever lost the right to stand in any kind of moral judgment of anyone, given the twin crimes of genocide against the Native Americans and slavery against the Africans -- crimes that dwarf nearly all 20th and 21st century crimes around the world. But I don't believe we're responsible for our ancestors, and I doubt you do, either. If someone were to suggest that we lack standing to criticize Al Qaeda, for example, thanks to those crimes of the 17th, 18th, and 19th centuries, I'm sure you'd reject that, even though the crimes of Al Qaeda don't come anywhere close to the magnitude of the crimes of earlier Americans.