The deadly terror attacks in Paris sparked a heated political debate in the U.S. on Monday as policymakers sparred over President Barack Obama's plan to settle thousands more Syrian refugees in the country.
Republicans on Capitol Hill threatened to block a previously announced White House effort to welcome 10,000 Syrians next year, and some GOP presidential candidates called for a prohibition on anyone fleeing Syria from reaching American shores.
Debate over Washington's role in the widening European refugee crisis had been simmering for months, but the attacks in France on Friday that killed at least 129 people shifted the focus to the Islamic State, which has claimed responsibility.
"The national security of the American people demands that the Congress swiftly extinguish any programs that might allow an ISIS terrorist to infiltrate the United States disguised as a refugee or migrant," Republican Ben Carson, a retired Johns Hopkins neurosurgeon and leading contender for the GOP nomination, wrote to congressional leaders Monday.
Democrats, including Obama, defended the expanded refugee program, noting that millions fleeing ISIS-held territory in Syria and Iraq are trying to escape the kind of violence that has shaken Paris and the world. They also said the U.S. more vigorously vets refugees than Europe, in a process that can take as long as two years.
Sen. Ben Cardin, the top Democrat on the Senate Foreign Relations Committee, called efforts to halt the refugee program "misguided."
"We need to strongly vet any resettlements in the United States — and we do."
Speaking at the G20 summit in Turkey, Obama specifically addressed comments by Republican presidential candidate and former Florida Gov. Jeb Bush, who said in an interview on CNN over the weekend that the U.S. should "focus our efforts" on Christians being persecuted in the region.
"When I hear political leaders suggesting that there would be a religious test for which a person who's fleeing from a war-torn country is admitted, when some of those folks themselves come from families who benefited from protection when they were fleeing political persecution — that's shameful," Obama said, without mentioning any candidate by name.
"That's not American," he added.
The idea also drew criticism from social service organizations who have been helping refugees overseas and at home, such as Baltimore-based Catholic Relief Services.
Bill O'Keefe, the group's government relations director, argued it would be far more difficult to prove someone's religion than it would be to ensure that they are not a terrorist.
"Politicians need to work together to find solutions rather than using these attacks to score political points," he said.
"The idea that terrorists would exploit the resettlement process to infiltrate the U.S. is so far-fetched that it doesn't pass the laugh test," said Kathleen Newland, co-founder and senior fellow at the Washington-based Migration Policy Institute. "The refugees who come through the refugee program have been … vetted through the course of a year or two by three or four U.S. government agencies independently."
As critics in Washington considered legislation to block the program, more than a dozen governors — most of them Republican — said they are opposed to Syrian refugees arriving in their states. They included the governors of Illinois, Ohio, Florida and Texas. New Hampshire Gov. Maggie Hassan urged Washington to halt the resettlements — adding a rare Democratic voice to the mix.
Hassan is running against an incumbent Republican for U.S. Senate.
Governors have little power to bar refugees from entering their states — a fact underscored by last year's surge of Central American children crossing the U.S. border with Mexico. Then, as now, the federal government generally places refugees with locally based, non-profit service organizations.
Maryland Gov. Larry Hogan, a Republican, said his administration would study the issue.
"We are going to make a very reasoned and careful decision about what we do here in Maryland," Hogan said at a news conference in Annapolis on Monday.
Rep. Andy Harris, the state's only Republican in Congress and a member of the House Appropriations Committee, called for a "strict vetting process" that prioritizes "Christians and Yazidis who are escaping religious persecution."
An aide said Harris is open to exploring the idea of stripping funding for the program out of a must-pass federal spending bill now under negotiation. Several GOP lawmakers have suggested such a strategy.
Refugees who wish to resettle permanently in the United States submit to a lengthy process that includes background checks by the Department of Homeland Security, fingerprinting and health screenings, experts said.
Once refugees have been cleared for arrival, they are assigned to a refugee resettlement organization, such as the Lutheran Immigration and Refugee Service, which is headquartered in Baltimore, or the International Rescue Committee.
About 70,000 refugees will be resettled in the United States this year. Between 2010 and 2014, Maryland took in 6,700 refugees, with Baltimore taking the largest share.
Michael Mitchell, vice president for programs with the Lutheran group, said screening has become even more intense since the 2001 terror attacks in the U.S.
Despite the political backlash since the Paris attacks, he said, many Americans, particularly churches, have stepped up to support new Syrian refugees.
"There is a commitment by a lot of people to ensure that they integrate into the society," he said.
"If more Americans saw the image of Syrians who are here and grateful to participate in American society, they would not be fearing Syrians, they would be asking, 'How can we welcome more,'" Mitchell said.
Millions of Syrians have been displaced by the ongoing resistance to the Assad regime, creating the largest migration crisis in Europe since World War II.
On Monday, Islamic State militants released a video that praised the Paris attacks and threatened similar action in Washington. Police suggested that lawmakers and aides working on Capitol Hill use underground tunnels to get around "out of an abundance of caution," but cited no specific threat to the complex, according to the Associated Press.
The video prompted Carroll County public schools to suspend field trips to Washington.
Under pressure from other Democrats and human rights groups, the Obama administration committed to accept 10,000 refugees from Syria next year — up from the 2,000 it took in this year. The U.S. has sent $4.5 billion in humanitarian aid to the Syrian people, the largest amount offered by any nation.
In September, Former Maryland Gov. Martin O'Malley became the first presidential candidate to call on the U.S. to accept 65,000 Syrian refugees. The Democrat stuck by that number in his party's second presidential debate on Saturday, and he was campaigning on the issue at events in Iowa on Monday.
"The best way to respond to the despicable attacks in Paris is to defeat ISIL and be a moral leader of nations," O'Malley said in a statement, using a different acronym for the Islamic State. "That means not only working in smarter and more collaborative ways with our allies and partners to eliminate the terrorist threat, but also staying true to our values."
Baltimore Sun Media Group reporter Lauren Loricchio contributed to this article.