Congress, no stranger to polarization, finds itself divided on the subject of military intervention in Syria.

Sen. John McCain has called for the U.S. to launch airstrikes to stop the violence in Syria. Several of his Senate colleagues have joined him.

Others in both parties, weary from a decade of war, are more reluctant to get involved.

Syria's relentless crackdown on anti-government rebels is about to enter its second year. An estimated 7,500 Syrians are dead, with no end in sight.

Though the U.S. is weighing its options, from arming rebels to using force directly, some military experts are calling for caution, saying U.S. action against Syria would come with a lot of risk.

Defense Secretary Leon Panetta says the situation in Syria is very different from the one in Libya, where the U.S. helped force out Muammar Qaddafi. According to Panetta, Syria's air defenses are far more sophisticated than Libya's, with a chemical and biological weapons stockpile 100 times larger.

An air campaign would have to be sustained over an extended period of time with a significant number of aircraft, Panetta said, saying he would weigh carefully whether or not the mission could be achieved before putting "our sons and daughters in uniform in harm's way."