Who's to blame and who's responsible for fixing it

Wednesday's David Leonhardt column is terrific for its clarity and fairness. His two "basic truths" about the deficit:

The first is that President Obama's agenda, ambitious as it may be, is responsible for only a sliver of the deficits, despite what many of his Republican critics are saying. The second is that Mr. Obama does not have a realistic plan for eliminating the deficit, despite what his advisers have suggested.

Here he goes through the methodology. And here's a pie chart by Matt Yglesias: