How many times has that been tried before? America with Vietnam, that was even a real war. They put alot of heat on them yet the vietcong did not back down. Or Russia and Afghanistan, they bombed their houses, they had military superiority yet the taliban did not fear them nor run from them.
What makes you think you can scare these people? You put on those tactics and they will do the same. They will attack you even harder, try to scare you. Next you know another terrorist attack happens and thousand of people die.
Its hard to fight fire with fire. You can scare one guy and hunt him down but these people are not sane. Another one will take the job. You dont think that the new CEO for AQ doesn't know the risks? He does and he still believes in his own cause. That is what blind faith does to you. Not even death can stop these people. Therefor another way of thinking has to be embraced.