Spoiler

Krugman nails it again:

[O]ne non-rank-and-file Republican, Senator John McCain, is apparently playing spoiler. Earlier this week, while refusing to say whether he supported the Paulson plan, he claimed not to have had a chance to read it; the plan is all of three pages long. Then he inserted himself into the delicate negotiations over the Congressional plan, insisting on a White House meeting at which he reportedly said little — but during which consensus collapsed.

If you need convincing that all of this matters, see this. The key point left open is:

... placing everyone who depends on credit under strain.

The bursting of the housing bubble has strongly deflated housing prices. The deleveraging of financial institutions and the parallel flight of credit to T bills is how deflation spreads throughout the economy.