Here's a $12 trillion question: Are money-market mutual funds safe?

The industry insists that they are and banking regulators aren't calling in the National Guard, although the U.S. Treasury Department is considering some emergency measures in case of a U.S. debt default.

Yet with the U.S. default risk hissing like a cobra, Congress and the White House at loggerheads and all the bad debt sloshing around Europe, is there a reason to be concerned?

Fear has reared its coiled head again. On Monday, stocks worldwide slumped on fears that Europe’s financial woes would spread to Italy.

If Congress doesn't raise the federal debt ceiling, the prospects that interest rates will soar and there will be a run on money-market funds rise dramatically. Everything from company payrolls to Chinese stocks may get gobsmacked.

The government guarantees enacted in 2008 for money-market mutual funds are no longer in place. Money market accounts offered by banks with FDIC insurance are still covered.