His caution — supported by a majority of Americans surveyed in recent polls — has angered some congressional Republicans and human rights activists while leaving European allies waiting for a clear sense of the direction he wants to take in Syria.
Most European leaders understand Obama’s domestic political motivation: He was elected as a president who would end America’s wars, not start new ones.
But Obama’s response to Assad will also be gauged by Iran’s leaders to assess how serious he is about stopping their uranium-enrichment program, which U.S. officials and their allies believe will be used to develop a nuclear weapon.
Nile Gardiner, director of the Margaret Thatcher Center for Freedom at the conservative Heritage Foundation, said Obama is “a bit late to the table” in expanding U.S. support to the rebels.
“His stance on Syria has been viewed in some parts of Europe, particularly Britain and France, as very weak and slow,” Gardiner said. “It’s perceived as if Obama had outsourced his foreign policy to the United Nations and Russia.”
After leaving Iraq and setting an end date for American combat operations in Afghanistan, Obama has sought to avoid a new war in a Muslim country, this one at the center of the Arab Middle East.
Obama intervened in Libya two years ago after securing Arab support, based largely on Moammar Gaddafi’s threats to massacre the restive population of Benghazi.
But Obama did so with a very low profile, lending U.S. military aircraft, ship-to-shore missiles and intelligence to a broad effort that featured European leaders as the face of the intervention.
A similar diplomatic approach has taken shape around Syria, although one defined by even more White House caution.
Some analysts said Obama’s decision to confirm Assad’s use of chemical weapons only days before the G-8 summit was designed, in part, to lessen the criticism he was likely to receive from some of his European counterparts.
British Prime Minister David Cameron pushed successfully last month for the European Union to lift its embargo on sending arms to Syria’s rebels, preparing the way legally for the British and French to begin doing so.
But Cameron has not yet decided whether he will send arms, and he has said that he would seek approval from parliament for any proposal to directly arm Syria’s opposition.
Obama administration officials have also not specified what kinds of weapons the government intends to provide Syria’s rebels, a loose confederation of forces, including a number of powerful factions guided by Islamist extremism.
Rhodes, the deputy national security adviser, said earlier this week that “we are aiming to be responsive to the needs of the Syrian opposition.”
To what degree remains unclear. Syrian rebel leaders have sought antitank, antihelicopter and antiaircraft weapons that many European governments are reluctant to supply for fear they will fall into the wrong hands.
“We’re not yet clear on what the policy response will be,” said the Western diplomat, referring to Obama’s response. “The specifics of what, when and how is not yet clear. What we’re all clear about is that we need a political process.”
Will Englund in Moscow contributed to this report.