I dont know if I'd got as far as his policies have played out correct. I would say he had a number of general ideas that were accurate (e.g. hard stance on China, getting Europe to pull more of their weight with NATO), but he had no clue how to work with other countries to accomplish those goals. Taking on China alone with the trade war instead of coordinating with our European allies, not working collaboratively with NATO to increase European funding, etc.
A few ideas were sound, the policies used to implement those ideas were not. One of his biggest problems is he didn't know how to work with people and always had to be the smartest guy in the room.