McCain's statement on the Senate floor came as the U.S. and European governments pleaded for Russia's Vladimir Putin to rethink his anti-interventionist stance on Syria, in what appeared to be an increasingly desperate effort for consensus among world powers to stop a crackdown that has killed more than 7,500 people. Hundreds fled to neighboring Lebanon on Monday fearing they'd be massacred in their homes.
But the trans-Atlantic calls for Russia to abandon its opposition to strong U.N. action were delivered at a curious time: a day after Putin showed his strength by resoundingly winning re-election to the position he held from 2000 to 2008. Even the modest aim of gaining Russian support for a humanitarian strategy in Syria faced renewed resistance Monday -- showing just how limited the diplomatic options were despite the ongoing violence.
McCain's strategy would be far more direct, though it's unclear how popular it would be. His statement was as much a critique of President Barack Obama as a rallying call for an international military campaign, accusing the president of being too soft on Assad.
McCain, the GOP's presidential nominee in 2008 and his party's senior member on the Senate Armed Services Committee, said the U.S. should change policy by arming Syria's rebels and spearheading a military effort to support them.
"The only realistic way to do so is with foreign airpower," McCain concluded. "The United States should lead an international effort to protect key population centers in Syria, especially in the north, through airstrikes on Assad's forces."
McCain's proposal will likely divide American lawmakers, many of whom opposed a similar operation in Libya last year. Even if it were championed by the Obama administration and its NATO allies, the plan would divide other countries hostile to the Assad regime but unwilling to support another Western military intervention in the Muslim world. And it would be anathema to Russia, which sees Syria as its primary ally in the Middle East.
Unlike the international Libya campaign that ousted Moammar Gadhafi in Libya last year, military action against Syria would not have the backing of the U.N. Security Council and would be difficult to justify under international law. In many ways, it would also be a rejection of Obama's doctrine stressing international collaboration on applying military force.
Obama's strategy has been to use sanctions and international diplomatic isolation to pressure Assad into handing over power as part of a political transition. At the minimum, Western countries want aid guaranteed for civilians caught between Assad's forces and the increasingly militarized opposition, but are struggling even to convince Damascus and its Russian and Iranian backers of that.
Russia, alongside fellow veto-wielding Security Council member China, has stood by Assad even while his forces have killed thousands over the past year, rejecting two U.N. resolutions critical of the Syrian government. Negotiations on a narrower, third resolution are ongoing in New York, and the Kremlin again seems to be standing in the way.
"I hope that Russia now, after the elections and with a clear view, will see that it stands on the wrong side of history," said German Foreign Minister Guido Westerwelle. "The people in Syria who are standing up for democracy and their freedom need solidarity from the international community."
Speaking in Prague, EU foreign policy chief Catherine Ashton said an Arab League meeting this weekend would offer Putin a chance to work with the rest of the world on getting humanitarian assistance into besieged cities such as Homs, and recognizing "that there needs to be a new leadership in Syria."
State Department spokeswoman Victoria Nuland said Washington planned to immediately take up the Syrian issue with Moscow. She said the U.S. is open to compromise on U.N. action as long as Russia stopped trying to equate the Assad regime's violent repression of protesters with rebels trying only to defend their communities.
"We hope that their sense of humanity and compassion will encourage them to join us in pressing the Assad regime to silence its guns," she said.
The entreaties failed to make an immediate impression on Moscow. Foreign Minister Sergey Lavrov instead drew attention to a months-old Russian resolution demanding that Syria's government and the opposition hold talks on reforms. The Russian approach would keep the levers of power in Assad's hands, while requiring his opponents to end their rebellion.
"I don't think there is a need for any new initiatives," Lavrov said Monday. He said other countries "shouldn't expect one another to take any action, but sit down together and decide what steps need to be taken so that the Syrians stop shooting at each other."
Syria is Russia's primary ally in the Middle East, having maintained close ties with Damascus since the Cold War, when the Arab country was led by the current leader's father, Hafez Assad. Putin, Russia's prime minister for the past four years, called last week for government and opposition forces to pull out of besieged cities, accusing the West of encouraging the rebels to fight by refusing to make that demand.
Western countries, meanwhile, added to the pressure and isolation against Assad on Monday.
The Obama administration added Syria's state television and radio to a U.S. sanctions list for its role in supporting the crackdown, while Canada joined the list of governments that have closed their embassies in Damascus to protest the violence.
McCain's call for airstrikes was a marked change from his remarks last month, when he said the U.S. should find ways to help the Syrian people without putting American "boots on the ground." Then, he said the options included providing medical care and technical assistance to safe havens for refugees of the violence.
He had since called for arming Syria's rebels, another step the Obama administration is hesitant to take. It fears a further militarization of Syria, and says the government's superior firepower in the form of tanks and artillery means funneling weapons to Assad's opponents may neither save lives nor accelerate the end of the regime.
Associated Press writers Geir Moulson in Berlin and Laurie Kellman in Washington contributed to this report.