There might be a severe drought facing much of the nation, but billions of dollars in subsidies is soon to rain down on the bread-basket states, thanks to a farm bill signed by President Bush yesterday. Notwithstanding a White House pledge to wean farmers off of government funding, the bill is expected to cost $190 billion over 10 years, or $83 billion more than the cost of continuing current programs. A senior Republican official said Bush reversed course in the hopes of gaining an additional Republican seat in the Senate from one of the farm states next fall. The bill provides $17 billion for conservation measures. Still, it’s mostly bad news for environmentalists: Generous subsidies to huge factory farms further endanger the nation’s few remaining family farms. The practice of providing such subsidies dates from the early 1930s, when 25 percent of Americans lived on 6 million farms in the nation. Today, 2 percent of Americans live on 2 million farms.