Public workers may not be getting the retirement pay they've traditionally been guaranteed by contracts, laws and state constitutions. Last week, a federal bankruptcy ruling declared that Detroit's pension plans for city workers could be modified, just like any other debts owed by the city. That has other cities threatening to declare insolvency, in part to cut pension payments. But some Democrats, as well as Republicans, are already saying that state and local governments can't afford to make contributions any more. What's in store for firefighters, police officers, trash collectors and teachers who've accepted modest pay knowing their old age would be taken care of?