Arizona Sen. John McCain called Monday on the U.S. to lead international air strikes on Syria, according to the Associated Press.

McCain, a Republican in his fifth term in the Senate, said that the stakes are much higher in Syria than in Libya when the U.S. intervened last year and that the U.S. should intervene without United Nations approval, according to the New York Times.

If we were not to intervene “it would be a strategic and moral defeat for the United States,” McCain said.

In a half-hour speech to a nearly-empty Senate chamber, McCain said that time was running out.

“Assad’s forces are on the march. Providing military assistance to the Free Syrian Army and other opposition groups is necessary, but at this late hour, that alone will not be sufficient to stop the slaughter and save innocent lives. The only realistic way to do so is with foreign airpower,” he said.

McCain urged economic and humanitarian support for anti-government rebels last month, but this is the first time he has requested direct military support.

The protests in Syria have been met with a wave of violence originally resulting from a group of students who put up anti-government graffiti in mid-March 2011. The government has been cracking down on protest groups in recent weeks, which have lead to a portion of the military deserting and joining anti-loyalist rebel groups.