Editor’s Note: Peter Bergen is CNN’s national security analyst, a vice president at New America and a professor of practice at Arizona State University. He is the author of “Manhunt: The Ten-Year Search for bin Laden – From 9/11 to Abbottabad.”

Story highlights

Peter Bergen: The process of entering the U.S. as a refugee is so laborious that terrorists would likely choose other routes

He says visa waiver program needs some rethinking

CNN  — 

The fact that one of the Paris terrorists was posing as a Syrian refugee has caused some to ask whether one of the lessons of the Paris attacks is either to end or to “pause” accepting Syrian refugees into the States.

The U.S. House of Representatives overwhelmingly passed a bill Thursday to pause the relatively small number of Syrian refugees the United States is willing to admit –10,000 in 2016 — and adding a provision that the FBI director and other top government officials must certify that any refugee entering the States from Syria is not a threat.

There’s clearly real public concern about the issue. More than half of Americans polled by Bloomberg Politics said the United States shouldn’t take any Syrian refugees fleeing the terrible war in Syria. Many of the nation’s governors and GOP presidential candidates have also voiced their opposition to resettlement of Syrian refugees.

Terrorism scenario doesn’t make sense

Yet this entire kerfuffle doesn’t make much sense – because pretty much the last approach that any sensible ISIS terrorist would take would be to infiltrate the United States as a Syrian refugee.

Here’s why: First of all the ISIS terrorist would have to travel to a refugee camp in a country like Jordan or Lebanon or Turkey, joining the 4 million other Syrian refugees outside Syria.

Then he or she would have to be among those selected from the relatively tiny number of 23,000 refugees that the United Nations agency for refugees has flagged to the United States to be worthy for consideration to be admitted. Then he would have to be among the only 10,000 Syrian refugees the States is planning to admit next year.

According to the U.S. State Department, the vast majority of those admitted are children, women and the sick and the elderly, while only 2% admitted to the States are “military age males” between 18 and 30. The mathematical odds of an ISIS terrorist getting into the States through the Syrian refugee program are therefore miniscule.

Beyond the odds of all this happening, consider also the time this would take: The whole process of going to a refugee camp and then getting selected by the United Nations and then passing the battery of checks the U.S. government will put you through can take years.

Then consider the tests this terrorist would be subjected to as he attempted to clear the U.S. government screening process. As described by senior U.S. State Department official Anne Richard at a Senate Homeland Security Committee hearing on Thursday, a Syrian refugee trying to get into the States is scrutinized and/or interviewed by officials from the National Counterterrorism Center, FBI, Department of Homeland Security, State Department and the Pentagon.

Syrian refugees must also give up their biometric data, submit their detailed biographic histories and are also interviewed at length. These refugees are also queried against a number of government databases to see if they might pose a threat.

In the words of Leon Rodriguez, the director of U.S. Citizenship and Immigration Services, who also testified at Thursday’s hearing, of all the tens of millions of people who are trying to get into the States every year, “Refugees get the most scrutiny and Syrian refugees get the most scrutiny of all.” (Disclosure: I also testified at the same hearing about the composition of Western foreign fighters who are traveling to join ISIS in Syria, as well as about the scant odds that they could take advantage of the Syrian refugee program to get into the States.)

Less scrutiny for visa waivers

Surely there must be an easier way for terrorists to get into the States. The fact is that far less scrutiny is given to students arriving on student visas or nationals of countries that benefit from the visa waiver program, which allows citizens of many Western countries to visit the United States for up to three months without a visa, thus providing a backdoor way for potential terrorists to come to the United States from Europe.

In December 2001, British citizen Richard Reid took advantage of the visa waiver program when he attempted to bring down an American airliner flying between Paris and Miami with a bomb hidden in his shoe. Luckily the attack failed.

The fact that so many of the terrorists involved in the Paris attacks were French and Belgian citizens who had fought in Syria or were supporting that effort, at least one of whom appears not to have been on U.S. government watch lists, is the key fact to focus on from a U.S. national security perspective, not the fact that one of the attackers had posed as a Syrian refugee. Syrian refugees fleeing to Europe do not go through anything like the rigorous process experienced by those who are coming to the States.

If the Paris attacks have revealed a vulnerability in the U.S. visa system, it is the fact that European countries with some 4,500 of their citizens who have gone to fight in Syria often do not know who these fighters are or when they have returned to Europe.

If the European host countries don’t know who these fighters are it’s almost impossible for the United States to know who they are. They can be admitted under the visa waiver program if they haven’t made it onto a U.S. government watch list.

What this calls for is not ending or so bureaucratically jamming up the Syrian refugee program it effectively grinds to a halt, but a careful scrutiny of the visa waiver program to ensure it’s working as well as possible.

On Thursday Sens. Jeff Flake, R-Arizona, and Dianne Feinstein, D- California, said they plan to introduce bipartisan legislation for the 38 countries that are part of the visa waiver program to end visa waivers for anyone from those countries who has traveled to Syria or Iraq in the past five years. This is an eminently sensible proposal.

Pressure should also be brought to bear on European states to do a much better job of information sharing about who precisely their foreign fighters are, not only with the United States, but also with each other, as terrorists are taking advantage of the Schengen agreement that allows citizens of European Union states to cross Europe’s borders without being checked by border officials.

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