Well something we should make clear is that the GOP critics of Obama tried to sell the lie that executive orders/proclamations are unconstitutional. This is untrue. A President is well within his rights to issue orders or proclamations as long as they statutory standing in enforcing or implementing existing law and have constitutional validity.
If a Presidents EO or proclamation lacks either than the public has the remedy of filing suit in court. The court can overturn a Presidential EO if it lacks statutory standing or constitutionality.
In this particular case it appears that the Trump Administration did not adequately define its statutory basis for the EO and it appears that the order may include an unconstitutional religious test. In which case the courts are with in their rights as an independent branch of government to halt said Presidential E.O.
To me the irony (and hypocrisy) of the wingnut faction who cried and wet their panties that a Black President was playing King by issuing an EO. Now that the shoe is on the other foot they have no problems with EOs but are pissing themselves in rage cause they incompetently and ineptly rolled this one out and are now outraged that the judicial branch is actually doing its job.
I have no doubt some moron will start screaming "Judicial Activism!".
That would be our cue to start laughing.