Mario Loyola (sub. only) in the WSJ today:

As the Iran nuclear crisis enters its decisive phase, the West must put the military option back on the table. The terrifying consequences of this messianic regime’s acquiring nuclear weapons will become manifest the moment Iran withdraws from the IAEA: the possibility of nuclear terrorism, of medium-range missiles that could be nuclear-tipped, of mullahs who might feel less restrained by deterrence of any sort. Because of the intolerable uncertainties it would create, Iran’s withdrawal from the IAEA would be an act of aggression against those states that Iran so routinely and breezily threatens. As Henry Kissinger once said, it is sometimes necessary to threaten the use of force in order to avoid its use.
The last best chance to keep Iran from going nuclear may be to attach a trigger for military action to Iran’s refusal to cooperate with the IAEA. Even inside the Iranian regime, there are those who warn that such a refusal would be needlessly reckless. The West must strengthen their case by reserving the right to use force in defense of basic security. The Iranian regime and people may be united behind Iran’s right to nuclear technology, but they are not united behind the ruling hard-liners’ disregard for international law and national standing. Iranian officials have repeatedly insisted that they want to assure the world of Iran’s compliance with the nonproliferation treaty. That is the point the West can challenge the mullahs on.