WASHINGTON — The House voted overwhelmingly Thursday to drastically tighten screening procedures on refugees from Syria, seizing on the creeping fear stemming from the Paris attacks and threatening to undermine President Obama’s Middle East policy.
The bill, which passed, 289-137, with nearly 50 Democrats supporting it, would require that the director of the FBI, the secretary of the Department of Homeland Security, and the director of national intelligence confirm that each applicant from Syria and Iraq poses no threat. The bill’s fate is uncertain in the Senate.
The White House called the demands untenable and said that the president would veto the bill if it reaches his desk.
The sweeping majority of the House vote was a rejection of Obama’s moral appeal on the issue and the most vivid manifestation of the rapidly shifting politics within the United States, where Americans are at once war-weary yet also frightened by the threats made by the Islamic State.
More than two dozen governors, including one Democrat, have said they would try to block Syrian refugees from entering their state, and a recent Bloomberg News poll shows more than half of the nation agrees with them.
The House action also served as another blow to Obama on an area that has repeatedly bedeviled him over the last two years of his presidency — how to articulate and put in place a policy in Syria, where there are no clear paths or partners to end the conflict.
The fact that lawmakers in both parties have refused Obama’s request for an explicit authorization of force against the Islamic State, even as they vote to curb refugees, further highlights the vexing politics in the era of terror.
“People are very nervous, very worried about this,” House Speaker Paul D. Ryan said in an interview Thursday, referring to a town hall forum he conducted in a Wisconsin county that is split politically. “I think that people want to see that their leaders are taking this situation seriously.”
Two of the nine members of Massachusetts’ all-Democrat delegation voted in favor of the bill, Representatives Stephen Lynch of South Boston and William Keating of Bourne.
“I think the quality of the screening will improve,” said Lynch. “It may introduce some delay. The question is whether that delay will be substantial.”
Lynch added that he feels the bill balances “some inconveniences” for refugees against “some additional safety” for Americans.
Keating said the legislation “brings accountability into the process” and added that it should not slow the flow of refugees into the United States.
He added that the United States has little on-the-ground intelligence in Syria, underscoring the need to be careful when determining who from there can enter this country.
“We’re now just beginning to advance that,” he said.
In an e-mailed statement to the Globe, Representative Seth Moulton of Salem, who voted against the bill, said “shutting the door on Syrian refugees who are fleeing the very terrorists we’re fighting is inconsistent with our values and will not help us defeat ISIS.”
“I fully support increasing the security and effectiveness of the refugee program, but the bill on the floor today was not a serious effort to do so,” Moulton said. “It was a counterproductive measure that would add needless red tape to an already strong process.”
Obama even tried, without success, to persuade members of Congress on the issue during his trip to Asia by sending Twitter messages.
In a half-dozen tweets to his 5.1 million followers early Thursday morning, the president repeated his promise to “provide refuge to at least 10,000 refugees fleeing violence in Syria” after passing “the highest” security checks.
“Slamming the door in the face of refugees would betray our deepest values,” the president tweeted in defiance of the congressional action. “That’s not who we are. And it’s not what we’re going to do.”
Late Thursday, Senator Mitch McConnell, Republican of Kentucky, the majority leader, made a procedural move that would allow the Senate to take up the measure right after the Thanksgiving recess.
But its fate in that chamber is far from certain. On Thursday, Senator Harry Reid, a Nevada Democrat, vowed that Senate Democrats would serve as the administration’s firewall.
“Don’t worry, it won’t get passed,” he snapped.
Obama continued to emphasize that refugees were subjected to “the most rigorous vetting process that we have for anybody who is admitted.” He said the process of screening a potential refugee took up to two years and includes background checks by the national counterterrorism center, the FBI, and the Defense Department.
“That somehow they pose a more significant threat than all the tourists who pour into the United States every single day just doesn’t jibe with reality,” he said.
Annie Linskey of the Globe staff contributed to this report.