The problem is that with Trump the voiced ideologies are usually

• all hat no cattle
• don't count your chickens before they are hatched
• don't trust, then try to verify and find nothing real is happening

Further, even if he does truly believe in something, he has zero understanding of how to effect it as far as government is concerned. I feel it safe to say he hasn't a clue how to manage the Defense Dept. His only solution is to continually fire people (not for nothing that he became famous for that style of "management" on the teevee.) or get them to quit.

A more specific problem is that while he is voicing isolationist pieties in one place, he is saber rattling in ten other places. He just spent $72 million sending active duty troops to the southern border, for instance to fight a phantasm created out of whole cloth, without a second thought. Another example: whatever got bombed in Syria over the chemical attack thing, I am sure he ordered much more firepower and shock and awe used than was actually executed by the Pentagon behind his back.  I just don't buy that he's not a warmonger in his soul, sorry. I do suspect that if Kim ever said something bad about Trump's penis, our stock of bombs will be quickly depleted.