Leahy's comments echoed the views of dozens of lawmakers who left the briefing and said they want to see the resolution more closely resemble President Obama's own pledge that any strike be limited in scope.
"The president's request is open-ended," said Sen. Pat Roberts (R-Kan.), a former chairman of the Senate Intelligence Committee. "That has to be rectified, and they simply said in answer to that that they would work with the Congress and try to come back with a more prescribed resolution. But I'm not too sure that the people who answered that are the people that have that decision to make."
The briefing, held in the expansive Congressional Auditorium of the Capitol Visitors Center, crossed the two-hour mark shortly after 4 p.m. Some lawmakers exited the meeting in a rush to get to airports for flights home, but dozens remained inside the hall.
A quartet of administration officials, led by Deputy National Security Adviser Tony Blinken, presented evidence of the alleged chemical attack and then turned over the meeting to questions, alternating between Democrats and Republicans.
Lawmakers from both parties said there was widespread agreement with the evidence that Bashar al-Assad's regime carried out the chemical attacks -- but still doubt about whether U.S. military strikes would achieve a meaningful result.
"The evidence at this point is overwhelming," Rep. Sander Levin (D-Mich.) said.
Rep. Scott Rigell (R-Va.), who led the push to force a congressional vote on military intervention, said "80 percent" of the skeptics in the room doubted that a limited strike would achieve any clear result and might instead lead to bad consequences. "There is more a question of," he said, "is this the right approach?"
Rep. Cathy McMorris Rodgers (R-Wash.), the fourth-ranking House Republican, said lawmakers in the meeting expressed concern about "how limited and how focused any kind of a potential military action would be. I think they're seeking clarification about what exactly the president is proposing. There are concerns about the resolution being too broad."
"Members are becoming more informed and they're asking questions and that's all part of the decision," she said.
As head of the House GOP Conference, McMorris Rodgers potentially holds sway over several potential Republican votes. But she said she remains undecided.
"It's a difficult decision," she said. "I have a lot of concerns. I'm skeptical, but I'm going to listen and continue to learn."
Lawmakers who exited the briefing early also expressed skepticism about the presentation, saying they expect to hear more from the Obama administration in the coming days.
"There's more reading to do and that will happen over the course of the week," said Rep. Mike Quigley (D-Ill.), who said he was still undecided on how he would vote.
So is Rep. Scott DesJarlais (R-Tenn.), who said that, "I'm just not sure the case has been clearly made."
Quigley, DesJarlais and others canceled weekend plans and made quick arrangements for flights to Washington, but also planned to race home Sunday night.
"It's a pretty important issue, so I don't mind" coming back, DesJarlais said.
Many said they were eager to come back to Washington to review classified documents made available to them and also attend the in-person briefing.
Rep. Dennis Ross (R-Fla.) said he would wait to review reports by United Nations inspectors on the ground in Syria before making a decision. But he’s also worried that Obama might still strike Syria even if Congress rejects a use of force resolution.
"It's interesting that the president hasn't made Congress relevant at all in his administration until now. So if we don't approve it he might consider us irrelevant again and do what he wants to do," Ross said.
Others, like Rep. Linda Sanchez (D-Calif.), emerged to say the briefing had helped them decide how to proceed in the coming days. "It was certainly instructive, as classified briefings always are," she said.
"I'm glad I read the documents, it was worth the trip," said Rep. Bill Pascrell (D-N.J.). "I haven't really made up my mind. I'm not trying to be a wise guy, I just haven't."
Pascrell said he sensed that colleagues in both parties and chambers seemed to appreciate the seriousness of the decision they face in the coming weeks.
"People are coming in from all over the place, I'm from Jersey, I'm only three hours away," he said. "California is another story."
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