Dean Ing’s first novel Soft Targets (1979) suggested that against terrorists the most effective weapon is mockery. Since the London bombs I’ve seen hints of such an approach.
Arthur Silber (2006: that link is gone bad, here’s another) gets in a dig at another faction that favors indiscriminate violence:
. . . one has the sense that this kind of hawk (which is most of them now) can’t grasp the nature of a convincing argument. It is as if they believe that by shouting, over and over again, “But terrorists are really, really, really, REALLY evil!,” they will finally convince everyone who doubts or criticizes Bush’s foreign adventures that Bush is entirely right about everything. . . .