That program seems to be about addressing the issue of foreign terrorist fighters perhaps traveling after losing territory in the ongoing wars. vetting them more closely.
As we heard Trump really wanted to single out Muslims for extra vetting but that would probably be unconstitutional so the people who wrote the executive order for him just extended an existing one using protection against national security threats as it's intention thus making the order likely to endure.
Maybe they will add other countries in the future.
An alternative possibility is that the order was intended to create division with a number of scenarios mapped out.
Use it to undermine the legal institutions, lawyers representing those blocked and so on.
Trump staff can say they are getting in the way along with the crooked media.
If there is an attack of some sort they can blame judges and lawyers.
