Im not speaking of Al Qaeda. Sure, Iran could (will) give them a nuke, they could hit us and we coudnt prove it was them, but the answer there would be for GWB to say if we get hit, we will assume its from a hostile country.
Im not speaking of invasion or even taking actual military action. Im speaking of talking tough. If the Cold War taught us anything, its that sometimes simply saying "Bring it, mother!@#$er!" can go a long way. The fall of the U.S.S.R. was due, in part, to us saying those words.