what I'm getting at is maybe it will break their(the extremists) spirits, hopefully a short outburst and then they lose the will, but....you never know it may drive them harder
the latter is far more likely, man. what you forget is that the insurgents aren't a solid number of people. they aren't a clearly defined army we can isolate and take out. this could, in all likelihood, end up recruiting more insurgents and escalate the violence.
kill 'em all and let (their) god sort 'em out
which will do little but piss off muslims in other regions. then we'd have to go after the entire middle east. now we have no army to do this, our military is stretched too thin just in iraq let alone pushing into iran, saudi arabia, yemen, and wherever else. so we'd have to start using tactical nukes and risk a nuclear holocaust.
even supposing that doesn't happen, we'll be destroying the oil fields and reserves and basically collapse our own economy. make no mistake, the iraq war has fucked us over far more than the terrorists ever could have. this won't help.