So the US response to PR has been weak, disappointing, faulty, irresponsible, and down right hateful. It is not just the current idiot in office. There are other presidents since the colonization of the island (yes Obama too) who have contributed to a financial stranglehold on Puerto Rico. But check it out, you can help by calling your congress member and letting them know how you feel. Please follow DEFEND PUERTO RICO.
You can donate to them because they have Boricuas on the ground doing work, or you can put pressure on the US Govt. Check out these graphics by Michael Cordero, one of the co-founders.