U.S. lawmakers are scrutinizing the Obama administration's plan to admit 10,000 Syrian refugees to the United States, where the possibility of terrorist infiltrators is a top concern.
"If I could be assured these people could be vetted properly, I would be supportive," said House Homeland Security Committee Chairman Michael McCaul on ABC's This Week program. "We don't know who they are."
The plight of Syrian refugees has gripped the world's attention, including on Capitol Hill.
"These are refugees from torture, from murder, from killing, from genocide," said Republican Senator John McCain in a fiery floor speech last week.
With millions of Syrians displaced, the United States plans to admit 10,000 refugees. But even that tiny proportion is raising concerns.
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"From a national security standpoint, I take ISIS at its word when they said, in their own words, 'We will use and exploit the refugee crisis to infiltrate the West.' That concerns me," said Republican McCaul. "We have to deal with this crisis. But this could be a very reckless and dangerous policy."
The Obama administration says Syrian refugees will be thoroughly screened.
"We would not take any shortcuts when it comes to our security," said White House spokesman Josh Earnest. "So there will be an effort to try to accelerate that process or move more people through that process, but it will not come at the expense of the robust security precautions that will remain in place."
Even so, President Barack Obama's special envoy in the fight against the Islamic State acknowledges the potential danger is real.
"I think we should watch it," said retired General John Allen on This Week. "We should be conscious of the potential that Daesh [also known as the Islamic State] may attempt to embed agents within the [Syrian refugee] population."
Refugee proponents, meanwhile, say admitting 10,000 Syrians is a step in the right direction, but a number that barely begins to address the unfolding refugee crisis.