I would also point out that no Muslim refugee coming to the US has ever been involved in a domestic terrorist attack.
That's only because the Feds thankfully caught them before they could carry out such attacks. Here is a very recent one. So use arrests instead of attacks. Or do you want to wait until a big attack to admit there is a problem and risk?
http://www.cnn.com/2016/01/07/us/terror-charges-refugees/
"The arrests in Sacramento, California, and Houston did not appear to be directly related, but the cases had several similarities.
Both men were Palestinians born in Iraq and living as refugees in the United States, according to the U.S. Justice Department. And both of them are accused of lying to immigration officials about their alleged ties to terrorist organizations.
Omar Faraj Saeed Al Hardan, 24, of Houston, is charged with attempting to provide material support to ISIS."