Here’s a question for everyone.
If the Constitution of the United States can be looked at as a contract between the several states and the peoples they represent so as to form a unifying government aka the Federal Government. Then if the Constitution is set aside for whatever reason isn’t that contract then null and void?
And if it is null and void then any actions the Federal government takes at that point are what? Illegal? Piratical? Tyrannical?
In any case I can see the implementation of an executive order of this type as being in that vein. I just hope that this is another one of those boiler-plate just-in-case things like all of the thousands of “War Plans” the DOD comes up with like the invasion of Penguins from the Falklands on the shores of Florida, (Little tongue in cheek there).
A review of the events of 1860-1865 should answer your question.