CHUCK TODD (HOST): Now let's take a look at the big picture here. There's been nearly 785,000 refugees who have been admitted to the United States since 9/11. Only about a dozen -- roughly one one thousandths of 1 percent -- have been arrested or removed from the U.S. due to terrorism concerns. None of those folks removed were Syrian, by the way. The fact is, it's not easy to get into America via the refugee process. Let me walk you through how this works just with Syrians. The United Nations has referred just over 23,000 Syrian refugees to the United States. Of those 23,000, 7,000 of them were thought to be worthy enough to be interviewed by the Department of Homeland Security. By the way, they were interviewed outside the United States. And of those 7,000, just 2,165 were accepted into the United States. Now, here's the issue. The real vulnerability that U.S. lawmakers might want to look into is not the refugee process, it's actually those traveling to the U.S. on visas or with European passports. Let me explain. The visa waiver program allows passport holders of 38 countries who meet certain requirements to travel to the United States without a visa, without like a next level of vetting, that includes France, by the way, and many other European Union countries. So what does this mean? It's important to remember all 19 September 11th hijackers traveled to the United States on some form of a visa. None of them were refugees. It's this visa program that needs to be looked into by Congress.

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