US District Judge James Robart, who pointed out the obvious--the ban served to discriminate against Muslim people, but had nothing to do with any pressing threat from the seven countries indicated, because there was never any indication there had ever been a threat from those countries based on prior activity.
Trump, naturally, appealed this. The appeal was declined. Trump's response towards these decisions was basically, if anything happens for whatever reason post this decision--it falls on the judge who allowed "people pouring in". Meh.
It seems to me like appointing competent people to positions relating to national security, and maintaining a good relationship with and accurate information from the intelligence community, would be of more use than imposing a blanket ban on people from any specific region. It would be more easily defensible to collect information and rely on trained counter-terrorism professionals to use the information received, than to justify the restriction of travel by people who have already been cleared by various agencies.
Trump seems to believe that the job of the judiciary is to rubber stamp his whims. They rely on the Constitution, not his preferences, for their guidance--which is as it should be.
He does not seem to have a clear, historical understanding of this basic civic dynamic.