As said I find this proxy guilt thing very scary, btw my mother is still alive, it seems to me the logic of racism.
Show me someone that has joined their ethnic group, or that can choose to leave it. Guilt is too strong, perhaps - religion is a complex beast, after all - but an acknowledgement of that interdependency is required, I think, if we're to try and get a perspective on why these things happen in order to prevent them happening again.
The undue respect given to faith positions and organised religions is part of the problem in how we address the issue of religious violence and extremism. That we have to pretend there's a valid differentiation between 'good i.e. moderate' interpretations of beliefs and 'bad i.e. extreme' interpretations of beliefs as thought that were anything more than an aesthetic account is ludicrous.
We say extremism when we mean 'a version that doesn't comply with modern sensibilities' rather than any sort of doctrinal or creed position. If there's no means to differentiate, externally (or internally), any sort of validity for these positions, then they aren't functionally any different, we're classifying them by our impact on us, not on any inherent justification.
O.