LEHRER: Mr. President, new question. Two minutes. Does the Iraq experience make it more likely or less likely that you would take the United States into another preemptive military action?

BUSH: I would hope I never have to. I understand how hard it is to commit troops. Never wanted to commit troops. When I was running -- when we had the debate in 2000, never dreamt I'd be doing that.

But the enemy attacked us, Jim, and I have a solemn duty to protect the American people, to do everything I can to protect us.

I think that by speaking clearly and doing what we say and not sending mixed messages, it is less likely we'll ever have to use troops.

But a president must always be willing to use troops. It must -- as a last resort.

I was hopeful diplomacy would work in Iraq. It was falling apart. There was no doubt in my mind that Saddam Hussein was hoping that the world would turn a blind eye.

And if he had been in power, in other words, if we would have said, "Let the inspectors work, or let's, you know, hope to talk him out. Maybe an 18th resolution would work," he would have been stronger and tougher, and the world would have been a lot worse off. There's just no doubt in my mind we would rue the day, had Saddam Hussein been in power.

So we use diplomacy every chance we get, believe me. And I would hope to never have to use force.

But by speaking clearly and sending messages that we mean what we say, we've affected the world in a positive way.

Look at Libya. Libya was a threat. Libya is now peacefully dismantling its weapons programs.

Libya understood that America and others will enforce doctrine and that the world is better for it.

So to answer your question, I would hope we never have to. I think by acting firmly and decisively, it will mean it is less likely we have to use force.

LEHRER: Senator Kerry, 90 seconds.

KERRY: Jim, the president just said something extraordinarily revealing and frankly very important in this debate. In answer to your question about Iraq and sending people into Iraq, he just said, "The enemy attacked us."

Saddam Hussein didn't attack us. Osama bin Laden attacked us. Al Qaida attacked us. And when we had Osama bin Laden cornered in the mountains of Tora Bora, 1,000 of his cohorts with him in those mountains. With the American military forces nearby and in the field, we didn't use the best trained troops in the world to go kill the world's number one criminal and terrorist.

They outsourced the job to Afghan warlords, who only a week earlier had been on the other side fighting against us, neither of whom trusted each other.

That's the enemy that attacked us. That's the enemy that was allowed to walk out of those mountains. That's the enemy that is now in 60 countries, with stronger recruits.

He also said Saddam Hussein would have been stronger. That is just factually incorrect. Two-thirds of the country was a no-fly zone when we started this war. We would have had sanctions. We would have had the U.N. inspectors. Saddam Hussein would have been continually weakening.

If the president had shown the patience to go through another round of resolution, to sit down with those leaders, say, "What do you need, what do you need now, how much more will it take to get you to join us?" we'd be in a stronger place today.

LEHRER: Thirty seconds.

BUSH: First of all, of course I know Osama bin Laden attacked us. I know that.

And secondly, to think that another round of resolutions would have caused Saddam Hussein to disarm, disclose, is ludicrous, in my judgment. It just shows a significant difference of opinion.

We tried diplomacy. We did our best. He was hoping to turn a blind eye. And, yes, he would have been stronger had we not dealt with him. He had the capability of making weapons, and he would have made weapons.

LEHRER: Thirty seconds, Senator.

KERRY: Thirty-five to forty countries in the world had a greater capability of making weapons at the moment the president invaded than Saddam Hussein. And while he's been diverted, with 9 out of 10 active duty divisions of our Army, either going to Iraq, coming back from Iraq, or getting ready to go, North Korea's gotten nuclear weapons and the world is more dangerous. Iran is moving toward nuclear weapons and the world is more dangerous. Darfur has a genocide.

The world is more dangerous. I'd have made a better choice.