In a historical sense, NATO really is obsolete. It was a defensive alliance designed to deter the Soviet Union from attacking through the Fulda Gap and conquering West Germany. The threat of that ever happening disappeared when the Soviet Union dissolved, and there's no realistic scenario with that kind of military action happening again within the next fifty years.
However, NATO does more than that nowadays and it's become an extremely important instrument in cementing the power of the American Empire. Without NATO, the US will be greatly weakened both militarily and diplomatically. I can't imagine any president who understands how international relations works who would be interested in dismantling it. It'll be really interesting to see how much American power is going to be stripped away by Trump.
However, NATO does more than that nowadays and it's become an extremely important instrument in cementing the power of the American Empire. Without NATO, the US will be greatly weakened both militarily and diplomatically. I can't imagine any president who understands how international relations works who would be interested in dismantling it. It'll be really interesting to see how much American power is going to be stripped away by Trump.