...this article says why. Apparently, a significant fraction of these refugees are Al-Shabab cannon fodder. Al-Shabab, if you don't follow news from the Sandbox, is an offshoot of Al-Qaeda in the Arabian Peninsula.
Remember the Somali taxi drivers in Minneapolis who refused to take fares to bars or deliver bottles of booze to hotels (a normal part of cabbing)? Yeah, THAT group.
Remember Keith Ellison of Minnisota? Congresscritter of the leftward persuasion? Yeah, THAT Keith Ellison. His name will be linked in some fashion to Al Shabab, I'm certain of it. His tolerance and support of Somali refugees has caused many problems for the city he supposedly represents.
Any bets on the FBI looking into the whole Somali-gang thing in Minneapolis and elsewhere as to this link to overt terrorism?
I didn't think so.