It's hard to find any ethical basis in the Taliban, or in the sectarian violence in Iraq, or in suicide bombing in civilian areas, or indeed in any violence that targets civilians.
Yet, for the most part, the situations above involve motivation for a putative "greater good".
The concentric circles described yesterday, from yourself in the middle, to those closest to you next out, all the way to the rest of humanity who you don't know or care about too much, would seem not to apply to suicide bombers. If they're so ready to destroy themselves, they can't care too much about themselves or their loved ones.
Ahh, but that's the greater good at work. Yet it must be a perversion of any ethical framework that makes any claim to universality, if it involves killing people who are not directly waging war.
My instinctive feeling is that any credo that involves valuing those people not directly known to you, must have some aspect of universality. And those that don't value people in the distance, don't. Thus killers of civilians must have a corrupted ethical framework.
And conversely, there is some hope for a civilisation that invokes sanctity of human life. As Western liberalism does, albeit sometimes only nominally.
Violence always brutalises. Societal violence - capital punishment, corporal punishment - does too.