While investors in the United States have been preoccupied with the debt-ceiling crisis and volatile stock markets, the European Union debt crisis has worsened.
Now France is under suspicion, and if its debt troubles spiral out of control, then there's a good chance the country will take U.S. banks down with it.
Despite denials from the major ratings agencies, some believe France could be in danger of losing its AAA credit rating, just as the United States did recently.
In fact, it was Standard & Poor's unprecedented downgrade of the United States that put investors on notice that no nation was safe. France became a target because many of its large banks hold a lot of debt from troubled nations like Greece, and because France has a lot of debt of its own.
The cost of insuring French sovereign debt via credit default swaps edged up last week as rumors swirled and concerns accelerated.
French sovereign debt has grown alarmingly quickly, rising from just 64% of its gross domestic product (GDP) in 2007 to 85.3% of GDP this year, according to International Monetary Fund (IMF) estimates.
A weakening French economy - on Friday the French statistics office reported that second quarter GDP growth was zero - and inadequate government policies have added to investor jitters about the country's ability to repay its debt.
"We've been really cautious, and the sovereign crisis is now escalating," Philip Finch, global bank strategist for UBS AG (NYSE: UBS), told The New York Times. "It boils down to a crisis of confidence. We haven't seen policy makers come out with a plan that is viewed as comprehensive, coordinated and credible."