WASHINGTON — Secretary of State John Kerry asserted Sunday that the United States now has evidence of sarin gas use in Syria and said "the case gets stronger by the day" for a military attack.
A day after President Barack Obama stepped back from his threat to launch an attack, Kerry said in a series of interviews on the Sunday news shows that the administration learned of the sarin use within the past 24 hours through samples of hair and blood provided to Washington by first responders in Damascus.
"So this case is building and this case will build," Kerry said on NBC's "Meet the Press."
Kerry also said he was confident that Congress will give Obama its backing for an attack against Syria, but the former Massachusetts senator also said the president has authority to act on his own if Congress doesn't give its approval.
While Kerry stopped short of saying Obama was committed to such a course even if lawmakers refuse to authorize force, he did say that "we are not going to lose this vote."
Kerry said Obama has the right to take action against Syria, with or without Congress' approval. But he stopped short of saying Obama was committed to such a course even if lawmakers refuse to authorize force.
Congress is scheduled to return from a summer break on Sept. 9.
GOP Rep. Peter King of New York, who criticized Obama for not proceeding immediately against Assad, said the president may have trouble winning the backing of Congress.
"I think it is going to be difficult," said King, a member of the House Intelligence Committee, adding that there is an "isolationist" tendency in his GOP caucus.
Sen. Rand Paul, R-Ky., said he thinks the Senate "will rubber-stamp what he wants but I think the House will be a much closer vote." Paul said he believes "it's at least 50-50 whether the House will vote down involvement in the Syrian war."
But Rep. Mike Rogers, chairman of the House Intelligence Committee, called the evidence, including the fresh finding on sarin gas, "convincing and getting better." Rogers, R-Mich., predicted that "at the end of the day, Congress will rise to the occasion," but he also said "it's going to take that healthy debate to get there."
"This isn't about Barack Obama versus the Congress. This isn't about Republicans versus Democrats. This has a very important worldwide reach in this decision."
Obama, who has talked repeatedly of U.S. reprisals against President Bashar Assad for the alleged use of chemical weapons against his own people in Syria's protracted civil war, announced Saturday that he had decided to defer any immediate action in order to seek a congressional authorization.
"The case hasn't changed and the case doesn't change at all. The rationale for a military response is as powerful today" as it has been, Kerry said.
"This case is going to build stronger and stronger," he said. But he also said he thinks "the people of America should be celebrating that the president is not acting unilaterally."
Kerry maintained there is no weakness in the U.S. case underscoring Obama's about-face, saying instead that "the president believes that we are all stronger as a nation when we act together."
The secretary said that Assad "has now joined the list of Adolf Hitler and Saddam Hussein" in deploying chemical weapons against his population and that "the case remains the same" for a U.S. response. Kerry echoed Obama in saying the world cannot stand by and watch Assad use chemical weapons.
Asked if the U.S. obtained its new information from U.N. weapons inspectors who had visited Syria, Kerry responded, "No, it is independent. ... But it is confirmation of the signatures of sarin."
"In the last 24 hours," he said, "we have learned through samples that were provided to the United States, that have now been tested, from first responders in east Damascus, and hair samples and blood samples have tested positive for signatures of sarin."
He was asked repeatedly what Obama would do in the event that Congress refuses to give its consent, Kerry said, "The president has taken his decision."
"I think this is a smart decision by the president. ... He is not trying to create an imperial presidency," Kerry added. "I believe that in the end, Congress will do what is right."
Administration officials have said that Obama appeared set on ordering a strike until Friday evening. After a long walk in near 90-degree temperatures around the White House grounds with Chief of Staff Denis McDonough, the president told his aide he had changed his mind.
These officials said Saturday that Obama initially drew pushback in a two-hour session attended by Vice President Joe Biden, Defense Secretary Chuck Hagel, Director of National Intelligence James Klapper, CIA Director John Brennan, national security adviser Susan Rice and homeland security adviser Lisa Monaco. They declined to say which of the participants had argued against Obama's proposal.
Kerry appeared on NBC's "Meet the Press," CNN's "State of the Union," CBS' "Face the Nation," "Fox News Sunday" and ABC's "This Week." Paul was on NBC, Rogers was on CNN and King was on Fox.