Bankruptcy fears in Dubai and Greece roiled world credit markets in recent months as investors braced for the possibility of default. But United States governments have their own share of woes. The city of Vallejo, Calif., located just north of San Francisco, filed for bankruptcy in 2008. Jefferson County, Ala., is on the brink of what would be the largest government bankruptcy in the history of the U.S.--surpassing the 1994 filing by Southern California's Orange County. At least 39 states expect a budget shortfall in 2011 with the tab estimated at more than $180 billion. Free-spending America isn't quite a...