I think it boils down to the fact that Trump does not understand soft power. Slashing the most powerful and influential aid programme in the world shows that very clearly. The US is as rich as it is because they created an environment of stability (at least on their own territory) and ensuring that there are markets American companies can sell into.
Maybe not so much that as he sees everything as a bargaining chip and any unused chips as a waste. After all, bribery and favors are more or less what soft power is.
