I didn't take a stand on whether it was constitutional or not, I did try to make the case that DACA is not law. It is a policy implemented by a former administration via executive order. I suspect it would have been challenged if not intended as a temporary solution.

Fair is relative, it's going to be interpreted differently depending on which side of the argument you're on. Constitutionality if questioned can be resolved in the courts.

Seems like the rest of your post is an attempt to compare international travel and immigration. Not the same thing.