SNELLVILLE, GA – Just hours after President Obama described to a group of pro-Israel activists the steps he has taken and will take to prevent Iran from developing a nuclear weapon, Mitt Romney made a dire prediction about the consequences for that effort if the president is reelected.

"If Barack Obama gets re-elected, Iran will have a nuclear weapon and the world will change if that’s the case," Romney told a crowd of more than 1,500 in this suburb east of Atlanta.

Romney has stepped up his criticism of President Obama on foreign affairs, hitting the president for mission muddle in Afghanistan yesterday and continuing to label the president as weak regarding Iran, as he did today in response to a question from an eleven year-old boy.

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"This president failed to speak out when the dissidents took the streets in Tehran, he had nothing to say,” Romney said. “This is a president who has failed to put in place crippling sanctions against Iran. He's also failed to communicate that military options are on the table and in fact in our hand. And that it's unacceptable to America for Iran to have a nuclear weapon. I will have those military options, I will take those crippling sanctions and put them in place, and I will speak out to the Iranian people about the peril of them becoming nuclear."

This morning at the annual meeting of the powerful American Israel Public Affairs Committee (AIPAC), President Obama defended the steps his administration has taken to isolate the Iranian regime and derail its nuclear ambition, and he pushed back against critics like Romney who say he has not taken every action possible against Iran, or taken options like military strikes off the table.

"I have said that when it comes to preventing Iran from obtaining a nuclear weapon, I will take no options off the table,” President Obama said. “A political effort aimed at isolating Iran; a diplomatic effort to sustain our coalition and ensure that the Iranian program is monitored; an economic effort to impose crippling sanctions; and, yes, a military effort to be prepared for any contingency.”

"Iran's leaders should know that I do not have a policy of containment; I have a policy to prevent Iran from obtaining a nuclear weapon," the president continued.

Romney and Obama both mentioned Iran's Arab ally, Syria, in their remarks today, with the President Obama describing the Assad regime as "crumbling." Responding to a question, Romney said he did not support direct United States military intervention in Syria, but that otherwise the U.S. should be doing "everything in our power to encourage those looking for freedom in Syria."