It’s not just Trump. The US has always broken its treaties, pacts and promises
Well, the US is an unreliable international partner—and it has long been one, even before the current administration pulled out from the Trans-Pacific Partnership (TPP) and the Paris agreement on climate change, and threatened to end NAFTA. History is dotted with treaties that the US has signed but not ratified, signed and then unsigned, and even refused to sign after pushing everyone else to sign.
Capriciousness about international treaties is an old US tradition. It starts with the country’s very creation: hundreds of treaties signed with Native American tribes that were either broken, or not ratified. Today, the US is one of the countries to have ratified the fewest number of international human rights treaties—of the 18 agreements passed by the UN, America has only ratified five.