They think they can get rid of evil by throwing bombs at people who do particularly bad things. This is due to their complete ignorance of three basic facts:
1) The capacity for evil is in all of us. Even if every terrorist dropped dead right now, terrorism would not end.
2) They're attacking whole populations just to get a few of the bad apples. They're killing way more good, honest, hard-working civilians than they are bomb-toting terrorists.
3) Throwing bombs at terrorists is a really really really bad idea. About as bad as covering yourself in steak and jumping into a lion pit. You can't kill all the terrorists in one campaign. It simply can't be done, no matter how many smart bombs and Nintendo pilots you have. And when you kill some of them, that makes the others more pissed off at you. And when you bomb their countrymen, their countrymen get pissed off at you and are much more willing to join terrorist groups if they perceive it as the only way to seriously attack you.

Dealing with terrorists is a difficult issue, but the answer sure as hell isn't to set the terrorists' country on fire from the sky, for exactly the same reason that it would not have been acceptable to exterminate all the Germans in response to the Holocaust. Two wrongs don't make a right. Terrorism in response to terrorism is not acceptable behavior, because that makes you a terrorist. I do not dispute that terrorists deserve to die for their horrible actions against humanity. But I'm not going to limit myself to brown terrorists who don't believe in Jesus; Bush and Cheney are just as guilty of Osama and deserve the same fate as he does. Worse even, for they are responsible for far more preventable civilian deaths than Osama could ever dream of causing.