Puerto Rico’s descent into junk territory has been about as certain as death and taxes for a while now, but last night it finally happened. Ratings agency Standard & Poor’s cut the blue commonwealth’s debt to below investment-grade status, giving Puerto Rico membership in the very exclusive club of municipalities (less than one percent) with junk-rated debt. Other members include Fresno and Guam.The Wall Street Journal finds a couple of bright spots: Puerto Rico has taken steps toward reducing its budget deficit and reforming its ruinous pension systems, and the other two major credit-ratings agencies still have the island at the lowest level of investment grade. But this is cold comfort to San Juan, which will find its access to debt markets more constrained and its debt more expensive.We’re hoping for a recovery in Puerto Rico, but if it comes it won’t be quick. After decades of financial recklessness, you don’t hit rock bottom as quickly as you might like. And unfortunately, as a territory, PR can’t count on bankruptcy as an option.