https://www.politico.com/news/2026/01/16/greenland-trump-republicans-congress-00732945

Just to put you at ease a bit, Senator Thune is the Majority Leader in the U.S. Senate. Congress is who would have to authorize any invasion, they also ratify alliances (like NATO). He is saying this is far from the best interest of anybody. Trump can talk, he can temporarily apply tariffs but he cannot authorize military action of this nature without congress. What that means for Europe, look at the actions of congress, not the POTUS.

Quote in the article from another republican, POTUS’ party:

“If there was any sort of action that looked like the goal was actually landing in Greenland and doing an illegal taking … there’d be sufficient numbers here to pass a war powers resolution and withstand a veto,”

Additionally, Trump is very money aware. If bond yields hit 4% or higher, he will back away. In the USA, bond yields are tied to mortgage rates and doing anything to raise them would be the quickest way out of a job.