Gen. Colin Powell's enduring contribution to American foreign policy is the Powell Doctrine, defining when and how American military power should be used. The doctrine has three main precepts: Avoid mission creep, clearly define your goals, and plan an exit strategy before you go in. Obama's Libya intervention flunks on all three counts.

Avoid mission creep? It's too late. The mission has already crept. It was sold to us as a no-fly zone, designed to stop Moammar Gadhafi's air force from pounding rebel positions, evening the odds in the conflict. Of course, there would be a need to neutralize Gadhafi's air defenses to protect our planes as they patrolled the skies. But already it is clear that we are bombing everything in sight, crippling Gadhafi's armor, forcing his withdrawal from key cities and crippling his command and control structure. It is not a no-fly zone. It is full aerial warfare.

Defined war goals? The only one stated is to protect innocent civilians from Gadhafi's forces. How we are going to do this from the air is a question that remains unanswered. In any event, we are clearly confused between the goal of regime change on the one hand and protecting civilians on the other. Our aerial attacks have little to do with protecting anyone and everything to do with killing as many of Gadhafi's soldiers and disabling as much of his army as possible.

Exit strategy? The confusion over war aims and mission, as usual, becomes most apparent when it comes time to contemplate an exit. If our goal were simply to cripple Gadhafi's air force, that goal will be achieved very soon and we can pull out. But if the goal is to protect civilians, when will that goal be accomplished? Can it be reached as long as Gadhafi is in power? Not likely. So we really cannot pull out until we have changed the regime.

And then? What if Gadhafi is toppled but his forces are able and willing to wage an Iraqi-style insurgency, with attacks on civilian targets and the new government? Will we be forced to send in ground troops to accomplish our aim? How can we do so from the air?

And if Gadhafi does not leave and the regime is unchanged, are we prepared to go home without his resignation?

These questions are precisely the ones that Powell suggested be adjudicated before, not after, we have begun to attack. But in the fuzzy, wooly-headed thinking of this administration, one wonders if they were ever even asked.

The decision to attack Libya was made because NATO allies dragged Hillary into action when she toured their capitals last week. And Hillary -- along with Samantha Power and Susan Rice -- goaded Obama into action during a phone call on Tuesday night.

Obama needed Hillary's approval to go to war. He knows that since he was elected as a peace candidate, his own party will find it hard to support his entry into a new war, unless his erstwhile rival, Hillary, backs him up. In this case, it is not Secretary of State Hillary Clinton whose support Obama needs, it is nomination runner-up Hillary he wants by his side.

But, nevertheless, the fuzzy nature of our mission and the lack of an exit strategy make the possibility of an out-of-control engagement very real. And such a commitment, especially if it involves ground troops, will not sit well with Obama's base.

But, having made an investment in Libya, are we really going to be prepared to sit back and watch civilians get slaughtered by Gadhafi, in or out of power? Won't the same rationale that dictated the air offensive lead to ground troops? And won't Obama look insufferably weak if he fails to send them?

Obama has opened the door to disaster by his impetuosity in not asking the Powell Doctrine questions.