Steve Bannon is driving the agenda here. His mission as an avowed Leninist is to destroy the government. One way to facilitate this is to cause chaos by enforcing this immigration ban. Like Donald Rumsfeld , Bannon has create chaos with this ban, where no threat exists, and by doing so disrupts the world. There were weapons of mass destruction and none of these 7 Muslim countries have posed a threat domestically to America. 
Bannon loves war as well. Stands to reason that we can expect the United States to declare war in the near future. No wonder Trump wants Bannon to sit in all the security meetings. Bannon is driving the agenda.