Opting not to press the president over the timeline with which his administration responded to recent attacks in Libya, which has been a source of confusion and controversy over the last several weeks, Romney instead elected to launch a broader attack on Mr. Obama's vision for the Middle East and his response to the so-called Arab Spring.

"We can't kill our way out of this mess," Romney said, before calling for a "comprehensive and robust strategy" to help "the world of Islam and other parts of the world reject this radical violent extremism."

"With the Arab Spring, came a great deal of hope that there would be a change towards more moderation, and opportunity for greater participation on the part of women in public life, and in economic life in the Middle East," Romney said. "But instead, we've seen in nation after nation, a number of disturbing events. Of course we see in Syria, 30,000 civilians having been killed by the military there. We see in -- in Libya, an attack apparently by, I think we know now, by terrorists of some kind against -- against our people there, four people dead."

Returning repeatedly to Iran, Romney argued that the nation is "four years closer to a nuclear weapon" and that Mr. Obama has "wasted" the last four years because "they continue to be able to spin these centrifuges and get that much closer." He also said that, if president, he would "make sure that [Iranian President Mahmoud] Ahmadinejad is indicted under the Genocide Convention."

The president defended his actions in Iran, touting the sanctions his administration has imposed there as effectively bringing the nation to its "weakest point economically, strategically, militarily than in many years," and vowing to "continue to keep the pressure on to make sure that they do not get a nuclear weapon."

"That's in America's national interest and that will be the case so long as I'm president," he said.

Asked for a strategy to curb ongoing violence in Syria, Romney accused the president of punting responsibility to the United Nations, and said the U.S. should promote a policy that would "identify responsible parties within Syria, organize them, bring them together in a -- in a form of -- if not government, a form of -- of -- of council that can take the lead in Syria. And then make sure they have the arms necessary to defend themselves."

Mr. Obama, however, argued that while what is "taking place in Syria is heartbreaking," the U.S. should not be premature in arming Syrian rebels.

"We also have to recognize that, you know, for us to get more entangled militarily in Syria is a serious step, and we have to do so making absolutely certain that we know who we are helping; that we're not putting arms in the hands of folks who eventually could turn them against us or allies in the region," he said. "We are playing the leadership role. We organized the friends of Syria. We are mobilizing humanitarian support, and support for the opposition. And we are making sure that those we help are those who will be friends of ours in the long term and friends of our allies in the region over the long term."