But don’t we need to worry about government debt? Yes — but slashing spending while the economy is still deeply depressed is both an extremely costly and quite ineffective way to reduce future debt. Costly, because it depresses the economy further; ineffective, because by depressing the economy, fiscal contraction now reduces tax receipts. A rough estimate right now is that cutting spending by 1 percent of GDP raises the unemployment rate by .75 percent compared with what it would otherwise be, yet reduces future debt by less than 0.5 percent of GDP.
via Paul Krugman Blog – Lost Decade, Here We Come. Krugman on why you don’t cut government spending in a weak economy.