About 25 years ago in California, Orange Country went bankrupt and public employees had to do "give backs" of (if I remember correctly) about 1/2 of their retirement funds and other concessions.
I think that this will be the model for the future, but a state levels.
It may not seem fair to change the rules on public employees, but effectively the rules have changed for private employees because the economy at federal, state, local, and personal levels will keep getting worse.
When I was younger, I worked with techs working for the federal government and they received much lower salary, but a retirement. Now, they tend to make equivalent salaries and have more job security. I am as disgusted with unions lobbying Congress as I am with corporate lobbyists.