On Tuesday, Republican presidential candidate Rudy Giuliani accused his Democratic opponents of being weak on terrorism. “The Democrats do not understand the full nature and scope of the terrorist war against us,” Giuliani said. On Thursday, at their debate in Orangeburg, South Carolina, two of the three leading Democratic candidates did their best to prove Giuliani right.

During the debate, moderator Brian Williams of NBC News brought up Giuliani’s comment, and the candidates quickly pronounced it a “myth.” But Williams then turned to Sen. Barack Obama, second in the polls but gaining fast on the frontrunner, Sen. Hillary Rodham Clinton. “If, God forbid, a thousand times, while we were gathered here tonight, we learned that two American cities had been hit simultaneously by terrorists,” Williams said, “and we further learned beyond the shadow of a doubt it had been the work of al Qaeda, how would you change the U.S. military stance overseas as a result?”

The question was specifically focused on a military response, but Obama didn’t talk about the military, or any use of force at all. “Well, first thing we’d have to do is make sure that we’ve got an effective emergency response, something that this administration failed to do when we had a hurricane in New Orleans,” Obama said. “And I think that we have to review how we operate in the event of not only a natural disaster, but also a terrorist attack.”

“The second thing,” Obama continued, “is to make sure that we’ve got good intelligence, A, to find out that we don’t have other threats and attacks potentially out there; and B, to find out do we have any intelligence on who might have carried it out so that we can take potentially some action to dismantle that network.”

The reference to “some action” might be interpreted as an endorsement of the use of force, but in the rest of his response, Obama softened even that notion. “But what we can’t do is then alienate the world community based on faulty intelligence, based on bluster and bombast,” he said. “Instead, the next thing we would have to do, in addition to talking to the American people, is making sure that we are talking to the international community. Because as has already been stated, we’re not going to defeat terrorists on our own. We’ve got to strengthen our intelligence relationships with them, and they’ve got to feel a stake in our security by recognizing that we have mutual security interests at stake.”

That was it. Obama’s answer to a question of how, as commander-in-chief, he would change America’s “military stance” in response to an attack by al Qaeda did not involve using the military.

Williams then turned to former Sen. John Edwards, the strong third in the Democratic race. “Senator Edwards, same question: God forbid, two simultaneous attacks tonight, we knew it was al Qaeda. What would you change about U.S. military stance overseas?”

“Well, the first thing I would do is be certain I knew who was responsible, and I would act swiftly and strongly to hold them responsible for that,” Edwards said. “The second thing I would do, and some of these have been mentioned already, is find out how that this happened without our intelligence operations finding out that it was in a planning stage.”

Edwards offered nothing on how the United States might strike back. “How did they get through what we all recognize is a fairly porous homeland security system that we have in this country that has not been built the way it needed to be built?” he continued. “You know, did the weapons that created this — these two simultaneous strikes come through our ports? Were they in one of the containers that have not been checked? How did these weapons get here? And how do we stop this from happening again? I believe — and this goes to the question you asked earlier, just a few minutes ago — global war on terror. I think there are dangerous people and dangerous leaders in the world that America must deal with and deal with strongly, but we have more tools available to us than bombs. And America needs to use the tools that are available to them so that these people who are sitting on the fence, who terrorists are trying to recruit, the next generation, get pushed to our side, not to the other side. We’ve had no long-term strategy, and we need one, and I will provide one.”

Just as with Obama, there was nothing on a military response: One question, two leading candidates, and no explicit promise that either man would use military force in the event of not one but two more attacks on the United States by al Qaeda. It was only when Williams directed the same question to the Democratic frontrunner, Sen. Hillary Rodham Clinton, that the audience heard a suggestion that the United States might actually take military action if attacked. “I think a president must move as swiftly as is prudent to retaliate,” Clinton said. “If we are attacked and we can determine who was behind that attack, and if there were nations that supported or gave material aid to those who attacked us, I believe we should quickly respond.”

Clinton tempered her answer by saying the United States should not “go looking for other fights.” But she made clear she believes the use of force in response to attack is appropriate. “Let’s focus on those who have attacked us,” she said, “and do everything we can to destroy them.”

The weakness of Obama’s and Edwards’s answers appeared to concern some others in the Democratic field. A few minutes later, when New Mexico Governor Bill Richardson was asked a question on another topic, he quickly returned to the military issue. “I would respond militarily, aggressively,” Richardson said. “I’ll build international support for our goals. I’d improve our intelligence. But that would be a direct threat on the United States, and I would make it clear that that would be an important, decisive military response, surgical strike, whatever it takes.”

Still later, Sen. Joseph Biden dispensed with the limits of a “surgical” response and gave the Democrats’ only full-scale endorsement of military force. “Let’s stop all this happy talk here [that] the use of force doesn’t make sense,” Biden said. “The use of force in Afghanistan is justified and necessary; in Darfur, justified and necessary; in the Balkans, justified and necessary. You guys can have your happy talk, there’s real life.”

Thursday night was the first time Americans have had a chance to see the entire Democratic field together, responding to basic questions of national security. At the debate, Giuliani’s words seemed to hover over the proceedings. “I listen a little to the Democrats and if one of them gets elected, we are going on defense,” Giuliani said. In Orangeburg Thursday night, Barack Obama and John Edwards made precisely the same point.