Obama's decision to consult Congress came after lawmakers widely demanded he seek authorization under the War Powers Act. The specter of the Iraq war hovered too, with lawmakers skittish over the Bush administration's claim later disproved that Saddam Hussein's government possessed weapons of mass destruction.
"And all of us should be accountable as we move forward, and that can only be accomplished with a vote," Obama said Saturday. "And in doing so, I ask you, members of Congress, to consider that some things are more important than partisan differences or the politics of the moment."
Secretary of State John Kerry said the chemical weapons attack killed 1,429 people, of which he said 426 were children.
For now, many lawmakers were praising Obama for putting the question to Congress. But it is not expected to act until the House returns from recess Sept. 9.
"Under the Constitution, the responsibility to declare war lies with Congress," said House Speaker John Boehner in a statement. Boehner, who is second in line to the presidency, said his chamber would consider the question the week of Sept. 9.
"We are glad the president is seeking authorization for any military action in Syria in response to serious, substantive questions being raised," he said.
"The President's role as commander-in-chief is always strengthened when he enjoys the expressed support of the Congress," agreed the top Republican in the Senate, Mitch McConnell of Kentucky.
Rep. Peter King, however, said Obama was abdicating his role as commander-in-chief. King, R-N.Y., suggested the president was undermining the authorities of future presidents and seeking a political shield for himself by going through Congress.
"The president doesn't need 535 Members of Congress to enforce his own redline," he said.