It's not about legal arbitration/what we're beholden to by the document. It's a letter of intent. If Trump pulls out it could sow discontent worldwide and literally plunge the world into darkness (depending on how close you live to a coal fired power plant with zero regulations).
Trump could remain a signatory member, do absolutely nothing to achieve the set out goals or even do things counter to that goal, and still be fine in the eyes of the international community (They're banking on Trump not getting a second term). But if he does this now after Kyoto of past, we will definitely be ceding the future of any attempts to address this concern to the Europeans and the Chinese. We have already given the Chinese the TPP.
If Trump's goal is to isolate the US to the extent that our past partners ignore our requests for assistance in other significant areas and indeed start to cooperate with other trading partners in lieu of us, then sure. Leave the Paris Accords. America First.
