You do realize that not all refugees are Muslims. A large proportion are Christians fleeing certain death at the hands of the Islamic State. It is just that the press don't find the Christian refugees so interesting as they get fairly easily absorbed into the system.
I guess that depends on which statistics you believe. From what I've read a very small number of Christians have been let in through the refugee program. I think it's a nice idea to give Christians preference over Muslims because I think Islam not ISIS is at war with the west. But it doesn't work too well as a policy because it's easy to just lie or as Muslims call it al-Taqiyya and say you are a Christian. It's sad what's happening over there but it is the responsibility of the people who live there to fight ISIS especially the men. I think his list should of banned countries should get a lot bigger and include Saudi Arabia.