WASHINGTON - President Barack Obama is hitting the airwaves to try to convince war-weary Americans that limited strikes against Syria are needed for the United States' long-term safety, while his national security team is attempting to reassure skeptical lawmakers that the United States is not heading toward another Iraq or Afghanistan.
Obama on Monday planned to make his case for punishing Syrian President Bashar Assad for what the United States says was his decision to turn chemical weapons against his own people - a charge Assad denies in a new interview. Top administration officials are heading to Capitol Hill for more classified briefings. And White House national security adviser Susan Rice is scheduled for a speech at a Washington think tank timed to the public relations blitz.
In an interview Sunday in Damascus, Assad told American journalist Charlie Rose there is no conclusive evidence about who is to blame for the chemical weapons attacks and again suggested the rebels were responsible. Rose said Assad also warned him previous U.S. military efforts in the region have proved disastrous.
Kerry, appearing at a news conference Monday with his British counterpart, William Hague, vehemently denied Assad's assertions.
"We know that his regime gave orders to prepare for a chemical attack. We know they deployed forces," Kerry said. He added that the United States knows "where the rockets came from and where they landed ... and it was no accident that they all came from regime -controlled territory and all landed" in opposition-held territory.
"So the evidence is powerful and the question for all of us is what are we going to do about it. Turn our backs? Have a moment of silence?" Kerry said.
He said that if Assad wanted to defuse the crisis, "he could turn every single bit of his chemical weapons over to the international community" within a week. But he said that Assad "isn't about to do it."
Pressed further on Assad's denials, Kerry said, "I just answered that. I just gave you real evidence. Evidence that as a former prosecutor in the United States I could take into a courtroom and get admitted."
Obama will meet with Senate Democrats Tuesday to seek support for U.S. military action against the government of Syria, according to two Senate Democratic aides. The meeting at the Capitol would come just hours before Obama addresses the nation in a prime-time speech on Syria from the White House.
Former Secretary of State Hillary Rodham Clinton, who is scheduled to speak Monday at a White House event on wildlife trafficking, planned to reiterate her support of Obama's efforts to pass the Syria resolution, according to a Clinton aide who spoke on condition of anonymity because the person was not authorized to speak publicly.
With Congress set to have its first votes authorizing limited strikes into Syria as soon as Wednesday, Obama and his allies were arguing that the United States needs to remind hostile nations such as Iran and North Korea of American military might while working to reassure the nation that the lessons of the last decade were fresh in their minds.
"It is not Iraq, Afghanistan or Libya," White House chief of staff Denis McDonough said Sunday during one of his five network television interviews. "This is a very concerned, concentrated, limited effort that we can carry out and that can underscore and secure our interests."
But McDonough conceded the administration lacks "irrefutable, beyond-a-reasonable-doubt evidence" that skeptical Americans, including lawmakers who will start voting on military action this week, are seeking.
"It's an uphill slog," said Rep. Mike Rogers, the Republican chairman of the House Intelligence Committee, who supports strikes on Assad.
"I think it's very clear he's lost support in the last week," Rogers added, speaking of the president.
A survey by The Associated Press shows that House members who are staking out positions are either opposed to or leaning against Obama's plan for a military strike by more than a 6-1 margin.
"Lobbing a few Tomahawk missiles will not restore our credibility overseas," said Rep. Mike McCaul, the Texas Republican who chairs the House Homeland Security Committee.
Added Rep. Loretta Sanchez, D-Calif.: "For the president to say that this is just a very quick thing and we're out of there, that's how long wars start."
Despite public backing from leaders of both parties to strike, almost half of the 433 current members in the House and a third of the 100-member Senate remain undecided, the AP survey found. They will be the subject of intense lobbying from the administration - as well as outside groups that have formed coalitions that defy the traditional left-right divide.
Public opinion surveys show intense American skepticism about military intervention in Syria, even among those who believe Syria's government used chemical weapons on its people.
The United States, citing intelligence reports, says the lethal nerve agent sarin was used in an Aug. 21 attack outside Damascus, and that 1,429 people died, including 426 children.
Excerpts of Rose's interview are to be released Monday on the CBS morning program that he hosts. The full interview is set to air on Rose's prime-time program on PBS.
Even before the interview was released, the White House criticized it.
"It doesn't surprise us that someone who would kill thousands of his own people, including hundreds of children with poison gas, would also lie about it," spokeswoman Bernadette Meehan said.
Top administration officials, including Kerry, Defense Secretary Chuck Hagel and U.S. ambassador to the United Nations Samantha Power, planned to brief lawmakers ahead of the Wednesday vote on a resolution that would authorize the "limited and specified use" of U.S. armed forces against Syria for no more than 90 days.
The measure bars American ground troops from combat. A final vote is expected at week's end and the House is expected to take up the issue the following week.
McDonough spoke with ABC's "This Week," CBS' "Face the Nation," NBC's "Meet the Press," CNN's "State of the Union" and "Fox News Sunday." Rogers spoke to CBS. McCaul and Sanchez were on NBC.
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Associated Press writers Jim Kuhnhenn and Ken Thomas contributed to this report.