Personally, I’m most worried about the balance sheets of the really big banks. For example, in recently released highlights from its so-called living will, JPMorgan Chase & Co. revealed that $50 billion in losses could hypothetically bring down the bank. (All big banks must provide their regulators with a living will to show how they could be shut down in an orderly fashion if near default.)…

What are the odds that JPMorgan would lose no more than $50 billion on assets of $4 trillion, much of which is complex derivatives, in a euro-area breakup, an event that would easily be the biggest financial crisis in world history?

A few officials see the storm coming. The Swiss National Bank should be commended for putting renewed pressure on Credit Suisse to increase its capital levels by suspending dividends. The Bank of England has set up emergency liquidity facilities, and continues to press for more bank capital, although it could do more.

The Federal Reserve should apply the same approach to big U.S. banks, with an emergency and across-the-board suspension of dividend payments, but it won’t. The Fed is convinced that its recent stress tests show U.S. banks have enough capital even though these tests didn’t model serious euro dissolution risk and the effect on global derivatives markets.