For people who might not understand how NATO actually works, here is a pretty good description. The key point is that NATO is a mutual defense treaty, not a contract between Europe and the US for defense services. The US military is not a mercenary force that provides defense services to paying customers. Our military is in Europe today because it is in our own interest to be there. No one owes us anything. Keep in mind that the only time NATO nations have deployed in support of a member nation was in 2001 when European nations deployed military forces in support of the United States. I would hope that someone in the administration – Secretary of State? Secretary of Defense? National Security Adviser? anyone? anyone? – would explain this to the President, but I guess that’s not how it works.

That’s not how it works’: Trump’s grasp of Nato questioned

President’s claim that Germany owes the US ‘vast sums of money’ shows a lack of understanding, says ex-Nato representative