Killing and dying for belief is also, of course, not entirely a new phenomenon.
David Aaronovitch takes a look at recent terrorism from a unique perspective, considering the question of which came first: the politico-religious cause or the violent aggression?
Aaronovitch outlines the characteristics of the two murderers Truman Capote had researched in his book In Cold Blood. He then considers Richard Reid, the failed 'shoe bomber':
Richard Reid fits almost all these criteria. The barrister Peter Herbert visited the unsuccessful 2001 shoe-bomber in prison in the United States. Reid, a former mugger, described to Herbert his desire to blow up the plane in purely political terms. Specifically, “the foreign policy of the US Government, which . . . had resulted in the murder of thousands of Muslims . . .”. But Reid was not born a Muslim, and his parents weren’t Muslims, nor did he come from a Muslim community. When he did convert in prison, he embraced the most extreme form he could find. “The sermons of [Abu] Hamza and others,” says Herbert, “gave him a greater understanding of how to interpret his faith in a way that supported the use of violence. It also reinforced his view about the scale of US aggression . . .” Reid, in other words, was violence in search of a cause, not the other way around.
'Violence in search of a cause' is likely a good way of describing a lot of terrorists. (And, more broadly, likely a good description of a lot of young men in general.)
I don't think for a moment that this explains the making of every terrorist. But some of them? Probably. If nothing else, this emphasises that the problem will have to be thought through and dealt with from a variety of directions. It is also a useful warning not to take the self-justifying statements of terrorists themselves without a hefty shovelfull of salt.