The 4 policymakers who could decide the 2012 election - by Ezra Klein

 "For every one-percentage-point decline in euro-area growth, history suggests growth in the rest of the world will take a 0.7% hit, 'with the U.S. seeing a somewhat smaller decline than other parts of the world.'"

That's David Wessel summarizing some research from JPMorgan. The main channel of contagion is financial. Exports to Europe are 1.2 percent of GDP. That's not nothing, but it's not that much. The bigger problem is that "European banks have lent more than $6 trillion to the rest of the world, twice as much as U.S. banks." Indeed, "European loans to the U.S. amount to about 10% of U.S. GDP."

I used to say that Germany's Angela Merkel and the European Central Bank's Mario Draghi were going to decide who America's next president was. If they saved the euro zone, it would be Barack Obama. If they let it fail, it would be Mitt Romney. Then Europe stabilized and I stopped saying it.

For more: Wonkbook: The 4 policymakers who could decide the 2012 election - The Washington Post