Yes, Trump was shifting and incoherent on a lot of policy issues; this led lots of people to decide to believe the position they liked while discounting the others on the same issue.

This probably wouldn't work with a candidate that wasn't both a political unknown and running against an opponent with very high negatives where people were (perhaps subconsciously) looking for an excuse to vote elsewhere, but it did work in the situation that actually existed in 2016.

Yes, about ISIS. I do agree the US has no place bombing people but that wasn't about regime change.

And what can I say, there's not much to expect from campaign talk, but when there are millions of lives at stake you may not want to go with mrs. "We came, we saw, he died".