I'm not sure what this column was about. 

Our dear columnist begins by suggesting there 'could have been a constitutional crisis' over the judge's order. But Pres. Trump did what every other President usually does when confronted with a judge that issues an injunction--His justice department appealed, and possibly the case may work its way up to the U.S. Supreme Court. 

So this column has a bit of the 'Albert Memorial is Still There' story in it.  

What about the U.S. Executive Branch carefully reviewing the order to make sure it is legal? That to me would seem to be a more relevant question. 

And yes, that fictitious person in Yemen may not have a right to enter the U.S. But someone who has been issued a visa (possibly with a fair bit of screening beforehand) ought to have the expectation that the U.S. won't arbitrarily cancel it.