Psst! Here's the secret about Greek debt drama

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What is next in Greece?

The first thing to know about the Greece story is that it's not really about Greece.

Not, at least, in the big financial picture, where the country's measly $242 billion economy is only a shade larger than Connecticut's, and where its debt, the equivalent of $360 billion, would be a rounding error of the nearly $18 trillion in U.S. obligations.

Why Greece and its likely debt default and possible exit from the euro zone matters is as a symbol—of how far the global community will go towards rescuing Greece from its debts, and ultimately, perhaps, for whether similarly debt-laden weak sisters in the euro zone should simply leave the union, go back to their original currencies, and inflate their way out of trouble.

For U.S. investors, then, the dollars and cents aren't particularly compelling, but the longer-term ramifications could be more meaningful.

"You always want to think about any volatility that could be created by a default," Quincy Krosby, market strategist at Prudential Financial, said in an interview. "It's one thing to say it's 'contained,' but investors heard that subprime was contained, too."

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Indeed, the contagion risks, like those posed by the subprime mortgage meltdown in the previous decade, are at the heart of the Greek melodrama.