Credit Default Swaps on Collateralized Debt Obligations
That's the name of the game.
United States' banks hold insurance obligations on Greek debt. The insurance they sold is referred to as credit default swaps (CDS). Greece's debt is collateralized, referred to as collateralized debt obligations.
The game is to bleed Greece to death, but without causing Greece to default. That way, U.S. banks' balance sheets won't be affected by having to pay out on the insurance they sold.