As both sides in Syria's civil war accused each other of using chemical weapons Tuesday, some lawmakers on Capitol Hill wasted no time in calling for the Obama administration to consider military action.
However, the drumbeat died down as the administration stressed the need for "facts" and real evidence before deciding how to proceed - a contrast to how the Bush administration reacted 10 years ago after using flawed intelligence about weapons of mass destruction as the impetus for the war in Iraq.
The hawkish reaction from members of Congress followed an intelligence briefing given to lawmakers where, CBS News' David Martin reports, one high level official called the use of chemical weapons in Syria "probable," going further than the administration's original assessment that there was a "potential" use of chemical weapons.
"There's, at least, a high probability they have used, either in -- most recently or in the past, some amount of chemical weapons," House Intelligence Committee chairman Rep. Mike Rogers, R-Mich., said on "CBS This Morning" Wednesday. "This is the time to act. Don't wait until we have 5,000 dead. That's too late." Senate Intelligence Committee chairman Dianne Feinstein, D-Calif., echoed Rogers' remarks Tuesday afternoon.
Also Tuesday, Sens. John McCain, R-Ariz., and Lindsey Graham, R-S.C., said, "We are extremely disturbed by reports that chemical weapons have been used today in Syria.
"If today's reports are substantiated, the President's red line has been crossed, and we would urge him to take immediate action to impose the consequences he has promised. That should include the provision of arms to vetted Syrian opposition groups, targeted strikes against Assad's aircraft and SCUD missile batteries on the ground, and the establishment of safe zones inside Syria to protect civilians and opposition groups," the two said in a joint statement.
By Wednesday afternoon, however, after President Obama and others weighed in, the call for action quieted down, and the claim that the "high probability" that chemical weapons were used, was overshadowed by the administration's measured response to the allegations.
The president, during a news conference in Jerusalem with Israeli Prime Minister Benjamin Netanyahu Wednesday, stressed that before any action will be taken, his "teams" will investigate the allegations in Syria.
"In Syria right now you've got a war zone. You have information that's filtered out, but we have to make sure that we know exactly what happened, what was the nature of the incident, what can we document and what can we prove," said Mr. Obama, who has previously stated that the Syrian government's use of chemical weapons would be a "red line" for possible U.S. military action.
"Once we establish the facts, I have made clear that the use of chemical weapons is a game changer," he added.
Earlier Wednesday, U.S. ambassador to Syria Robert Ford said during a House Foreign Affairs Committee hearing that the Obama administration has no evidence to support claims that chemical weapons were used.
"So far we have no evidence to substantiate the reports that chemical weapons were used yesterday," Ford said, later pointing out what Mr. Obama did: that the administration is investigating the reports.
Former Sen. Bob Graham, D-Fla., who chaired the Senate Intelligence Committee from 2001-2003 suggested that the administration needs to tread carefully before responding militarily, using the Bush-Iraq scenario as an example.
"In Iraq we were almost totally dependent on exiles as a source of information on weapons of mass destruction, and of course it turned out to be bogus information," Graham told CBSNews.com, suggesting that allegations from both sides in the Syrian conflict are not enough to act upon.
"I hope we have had enough penetration in Syria to be able to acquire the information from U.S. sources and not depend on third parties."
Anthony Cordesman, a security expert at the Center for Strategic and International Studies told CBSNews.com there would be no ambiguity if chemical weapons were used, pointing out that it's "probable that given the tensions and the politics, some of this reporting is false. If it isn't false, I'm afraid you'll know all too clearly."
"Without more evidence, you can get into all additional speculation but there may been a little too much of that already," he said.