President Bush on Tuesday signed a $630 billion spending bill that includes a $25 billion loan to the struggling auto industry. (Bush’s sign-off also marks the expiration of the offshore-drilling ban and keeps the federal government funded through Mar. 6, 2009.) The loan package — the biggest federal subsidy for Big Auto since the feds bailed out Chrysler in 1980 — is aimed at helping carmakers improve overall vehicle fuel efficiency to 35 miles per gallon by 2020, as authorized in the 2007 energy bill. But the money may be a time in coming: the Department of Energy has 60 days to set rules for loan qualification, and DOE Secretary Sam Bodman says it could take up to 18 months for any money to be doled out. Michigan congressfolk are pushing for funding to arrive within six months. But hey, maybe Americans don’t need so many cars anymore: according to government stats released Tuesday, U.S. driving dropped in July for the ninth month in a row. Oh, just leave us to our wishful thinking.