Stock markets held their nerve today despite the risk of economic calamity if the US fails to meet a deadline on borrowing limits that is just days away.
But analysts suggested panic may not be too far off as the clock ticks towards the prospect of the world's biggest economy defaulting on its debt.
Political deadlock between Barack Obama and Republican politicians opposed to his landmark healthcare plan means there is still no deal ahead of Thursday when the US Treasury will run out of authority to borrow money.
The absence of a widespread slump, despite the major global repercussions a default would have, suggested investors were betting on a deal being reached since the prospect of a failure to do so was simply too extreme to contemplate.
Traders appear reluctant to sell shares in anticipation of a default, and risk missing out should an agreement - which they seem to believe is likely - is reached.
Alpari market analyst Craig Erlam said: "That may be working for now, but with only three days to go until the deadline, it can only last for so long.
"If we go another 48 hours without a deal to avoid the debt ceiling being agreed, we could see the rate of selling pick up, and that comfort replaced with panic."
Michael Ingram, market strategist at BGC Brokers, said: "The world continues to drift towards a catastrophic US debt default. So awful is the prospect that no one in financial markets seriously thinks the US Congress will actually let it happen.
"They are probably right, of course, but it still feels that equity markets have been approaching this issue with unusual complacency."
Meanwhile, investors may also be perversely reassured that the partial US government shutdown - after an earlier missed budget deadline in Washington - will mean central bank support for the US economy continuing.
Markets have been in a state of anxiety for months over the prospect of the US Federal Reserve pulling away regular multibillion-dollar quantitative easing injections, which have supported the recovery.
The damage caused by the shutdown is seen as making this prospect less likely.
Mr Ingram said: "To me, the end result is global stock markets that look healthy but feel sick. Tension is building, which is not fully captured by the uptick in volatility."
The US crisis hinges on Republicans in Congress refusing to pass new spending or borrowing laws without concessions from the White House on the president's so-called "Obamacare" reforms, which they bitterly oppose.
It has already seen non-essential parts of the government shut down, with the economy already starting to feel the damaging effects.
But a breach of the debt ceiling has the potential to be even more serious for America and the world. Hopes last Friday that a temporary solution could be found melted away over the weekend.
Christine Lagarde, head of the International Monetary Fund, warned of a "risk of tipping, yet again, into recession".