Trump failed to convince other countries to continue going along because he's a simplistic zero-sum bully who barks orders, expects others to fall in line, and then throws a tantrum when they don't - rather than a tactful leader capable of maintaining the trust of a voluntary positive-sum coalition. That he's also been overtly attacking allies at the same time doesn't help convince anyone either - the new regime was attacking Canada straight out of the gate, and it's hard to explain attacking Greenland any other way than a Putin-favored plan to drive a wedge between us and our traditional allies.