No, it's much simpler: in an open society it is virtually impossible to defend against terrorism. In other words, you can't stop these things, even if you really want to once they are in the planning stage. The chances of foiling the attack or the attack being successful are about even. So the only way to get rid of these attacks is to either go for some kind of root-cause and to fix the problem before it can gain a foothold or to radically chance society.
I'd hope for the former but I fear it will be the latter.