The U.S. President began the NATO meetings by offending US allies. No one was surprised.

Defense News:

Hours after [the U.S. President] landed in Brussels, the Senate passed a non-binding measure, 97-2, that expresses support for NATO, its mutual self-defense clause and calls on the administration to rush its whole-of-government strategy to counter Russia’s meddling in the U.S. and other democracies.