What's happening in the headlines can affect you as an investor. Here's what's going on, what you need to know, and what you should do.

The cold, hard facts
Financial Times is reporting that investors are shunning European banks en masse. The term "uninvestable" is actually being brandished.

Some context
Eurozone banks as a whole hit a peak in February, and have fallen in value by more than 50% since then. Since the start of the 2007-2008 financial crisis, they were lower only for a few days in March 2009.

There's no great mystery here. European banks are much more likely to be exposed to high levels of distressed eurozone sovereign debt than, say, American banks. Add to that worries about increased capital requirements and the threat of another recession, and it's no wonder European bank stocks are getting knocked around.

What you need to know
A sovereign-debt crisis overseas that's still getting wound up. A mortgage-debt crisis here that still hasn't wound down. Big banks as investments are tricky devils even in the best of times (which these aren't). Compared to your straightforward company that makes an easily understandable product and sells it, banks are very complicated, with arcane assets and accounting wizardry at work that makes their balance sheets notoriously hard to read.

I'd suggest avoiding European banks at all costs, even those that might appear to be bargains on the surface. There's even talk of nationalization, which is rarely good for shareholders. And the big American banks, such as Bank of America (NYSE: BAC), JPMorgan Chase (NYSE: JPM), Goldman Sachs (NYSE: GS), and Morgan Stanley (NYSE: MS)? I’m not interested in giving them a try either.

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