This is the first big test for Trump. Should the court order be upheld, it will create chaos for worldwide travel.  The biggest concern is how international airport and Homeland security measures will hold up as people swarm to get out of the old country.  There is no room for failure as there is no excuse for it.  This is a Trump issue of his own making, and whether his decision affecting U.S. security will pass the test.  This will also not bode well for the court lifting the ban if a horrific event occurs.  If all goes well and runs smoothly, the political, judicial, and security systems, will have responded to rapidly changing events, disagreements, a potential crisis, which is indicative of a healthy democracy.