Well, he tore apart the US-German alliance, which maybe isn't the biggest win for the US. Not that I am fond of Merkel. But NATO kept the peace for 70 years or so and it didn't survive two days of Trump.
"Merkel: We can't rely on the US anymore. I have experienced this in the last days. We Europeans should take destiny in our own hands."
https://twitter.com/YanniKouts/status/868814107486679041
But he did great with the Saudis and sold them military equipment at a discount.