It’s actually a nice move of him. USA had built military infrastructure in Germany for billions and then he left, leaving behind said infrastructure. Now he wants to do the same thing in Poland. It’s like an economic guerilla tactic where you make small investment skirmishes while simultaneously destabilising the relations to the countries you just pulled out of. It’s an obscure tactic without a foreseeable benefit. It’s good for Poland so I’m a fan I guess.