President Barack Obama on Thursday prepared for the possibility of launching unilateral American military action against Syria within days as Britain opted out in a stunning vote by Parliament.
Facing skepticism at home, too, the administration shared intelligence with lawmakers aimed at convincing them the Syrian government used chemical weapons against its people and must be punished.
Despite roadblocks in forming an international coalition, Obama appeared undeterred and advisers said he would be willing to retaliate against Syria on his own.
"The president of the United States is elected with the duty to protect the national security interests in the United States of America," White House spokesman Josh Earnest said.
Even before the vote in London, the U.S. was preparing to act without formal authorization from the United Nations, where Russia has blocked efforts to seek a resolution authorizing the use of force, or from Capitol Hill. But the U.S. had expected Britain, a major ally, to join in the effort.
Top U.S. officials spoke with certain lawmakers for more than 90 minutes in a teleconference Thursday evening to explain why they believe Bashar Assad's government was the culprit in a suspected chemical attack last week. Lawmakers from both parties have been pressing Obama to provide a legal rationale for military action, to specify objectives and to lay out a firm case linking Assad to the attack.
Afterward, the House Democratic leader, Rep. Nancy Pelosi of California, pointedly sided with Republican Speaker John Boehner of Ohio in urging the administration to do more to engage with Congress on the matter, even as she expressed "my appreciation for the measured, targeted and limited approach the president may be considering."
She said in a statement she agreed with Boehner and other lawmakers who say the administration needs to consult more with "all members of Congress" — a reference to the limited circle briefed Thursday night — and provide "additional transparency into the decision-making process."
Suspected chemical attack
The high-level officials who spoke to the lawmakers offered more details of the suspected chemical attack and their