Collective guilt is one of those pernicious concepts, a tool to spur the individual to action by implicating him/her in crimes committed by others with whom they share certain characteristics. For example, some Americans ascribe collective guilt to Muslims for terrorism, some on the radical Left ascribe collective guilt to whites for systematic decimation of Native Americans. In an insightful comment, Sitaram mentioned how a society shares collective responsibility for atrocities committed by it. When one sees a society as a seperate entity aside from the sum of its individuals, perhaps it makes some sense. Although I would like to believe in the agency of the individual to affect the collective, the fact of the matter is that any single individual only has agency to act, but there is no guarantee of results. Thus, one fact that ancestors of a society committed atrocities should not stain the current society, even if it benefited from said atrocities. If one segment of a society committs an atrocity, can we really hold thier country-mates responsible for it? 

I think people like this idea because we believe that if only more people felt guilty, they would hold in check the potential evil present in every human grouping. We like people to keep thier own house in order. Even I would rather see us Muslims take care of our extremist problem in house. However, few Muslims accept the collective guilt argument applied to us, and to be fair, reports seem to show that many Muslims (at least the ones who aren't already terrorists) seem to not collectively blame Americans for Iraq nor Britians for pretty much every mess that thier empire created in the Near East. And while we're at it, those British sure did have a bona fide empire imposed by force, something America hasn't quite decided that it want's to do. But, then again let's even the field: "...those Muslims sure did have a bona fide empire(s) imposed by force." Let's not forget that while many like to use 'empire' as a bad word as a tool against the West, the Arabs built one of the most rapid empires in history. Its just that they later lost that empire, first to the Persians, then to the Turks and then to the Europeans. So what? Its the cycle of history, and it is history and not herstory because most of the actors involved were male. But, don't hold me responsible just because I belong to the collective male, you know.

So, when we want to hold people collectively responsible and guilty, let's think first about what our aims are in doing so, and what stains we ourselves have in our own history; vulnerability goes both ways, eh.