Puerto Rico had defaulted, ie missed payments on its bonds.
It cannot be made to declare bankruptcy like a corporation, ie,, it cannot be forced to sell/transfer assets such as roads and schools and parks to its creditors.
There is very very little news on this.
What is the market value on existing PR bonds? Zero? $0.01?
What about old Greek bonds?
Yes once the Greek government started letting massive waves of immigrants pass through or stay in their country that gained them favor with the top who provide credit. Expect lessening financial burdens on the Italian and Spanish governments also.