Puerto Rico's debt level exceeds the island's capacity to keep up with interest payments, never mind dig its way out from under the principle. The economy isn't growing and won't grow given the status quo. Bankruptcy isn't an option, so Puerto Ricans are voting with their feet. Hundreds of thousands have left the island, with many settling in Florida.
With a basket-case infrastructure and power out for the long haul on much of the island, many more will leave. If congress doesn't bail out the island or Wall Street doesn't engage in some serious debt renegotiation, the residents can simply walk away from the island's debt.
Trump's warning to the residents is another nudge in that direction.
I wonder if congress is giving any thought to the possibility that Puerto Ricans could be a tipping point for Florida elections. 121,000 votes separated Clinton and Trump in 2016. The Puerto Rican population of Florida now stands at 1 million and growing fast. What happens politically if a 1/2 million more Puerto Ricans resettle in Florida in the coming years?