The US has stepped back from the brink of a financial default after Congress approved a deficit-cutting plan at the last minute.
But it has failed to allay fears of a credit downgrade and does little to prevent future tax and spending rows.
In New York, Wall Street was invaded by protesters angry at budget cuts, part of the deal to raise the debt ceiling.
“The general sentiment here is that we think a people’s movement is needed to fight back, so we can take control of the things that affect our lives, every level of government,” said protester Larry Hales.
Signing the bill into law, President Obama said it would be wrong to balance the budget on the backs of those who had borne the brunt of the recession.
Speaking after the Senate followed the House of Representatives by passing the bill, he said a new congressional committee set up to examine the US deficit should consider tax increases.
The compromise deal followed long drawn-out negotiations between Democrat and Republican leaders. There had been warnings that failure would have shaken world markets and left the US unable to pay its bills.