Republican presidential contender Mitt Romney says that if President Barack Obama wins a second term, Iran will obtain a nuclear weapon.
Romney opened Saturday night's GOP debate with strong criticism of Obama, the Democrat he hopes to challenge in 2012. He says that a Romney administration would prevent Iran from obtaining a nuclear weapon _ even if that means using U.S. military forces.
Rival Herman Cain says he would not use military action but says he would move warships to the region to deter Iran. Instead, Cain says he would prefer to aid the resistance to Tehran to overthrow the regime.
And rival Ron Paul, a congressman from Texas, says any use of force against Iran would require approval from Congress.