How long and hard the battle?

Although apparently no one was killed, today's bombing in London still disrupted normal life in a significant way. Terrorist experts debated the effect of the bombing throughout the day. Although terrorism may be a major thorn in our side for some time to come, I can't help but think that there is no way these terrorists can succeed. The more frequent their attack, even though small, become, the greater will be our force in abolishing them. And if their attacks are significant like 9/11 or the worst case scenerio of a nuclear attack, the repercussions will be enormous, drastic, but effective. The bottom line is that we will win. It's only a question of how long and hard the battle will be.