There is an astonishing number of peer-reviewed studies that show how ineffective it is to ban or restrict immigration based on country of origin with the intention of stopping terrorism. This is an absurd piece of showmanship that spits in the face of American values and gives ISIS and other radical groups even more material to recruit with. We all know it's un-American and completely ineffective given that we have an incredibly difficult and long vetting system in the first place. The courts have spoken. End this nonsense. Read the Constitution.