Even scarier than Trump saying these things is the fact that a majority of the Republican base probably agrees with him.
The majority of Americans have always supported things that were blatantly unconstitutional. It doesn't matter what they support though, because we have a Constitution.
"John Marshall has made his decision: now let him enforce it!"
---President Andrew Jackson
And how did that work out?
The Supreme Court was ignored, the Trail of Tears happened, and Andrew Jackson never received a consequence except the critical commentary of historians.