Obama’s challenger believes there is more the U.S. should do.

“I’d take on diplomatic isolation efforts. I’d make sure that Ahmadinejad is indicted under the genocide convention. His words amount to genocide in citation. I would indict him for it. I would also make sure that their diplomats are treated like the pariah they are around the world," said Romney.

Governor Romney is referring to the remarks of Iranian President, Mahmoud Ahmadinejad, who has called for the destruction of Israel.

Both candidates believe that Iran’s nuclear program is a threat to U.S. national interests. Ari Ratner, a Principal at the Truman Project on National Security, says, by nature, American foreign policy is bipartisan, and preventing Iran from obtaining nuclear weapons is a clear example.

“American National interests don’t change so much from one administration to another. A lot of this (Romney's critique of Obama) is bluster, desire to look tough," he said.

Iran says its nuclear program is for peaceful purposes and has no military component. But Yukiya Amano, the head of the International Atomic Energy Agency, United Nation’s nuclear watchdog, says the agency needs clarifications in 12 areas before it can confirm Iran’s claim.

While the American candidates spar over how to deal with Iran’s nuclear ambitions, Israel Prime Minister, Benjamin Netanyahu, is losing patience with Washington’s approach.