A deal better be on its way to completion by Thursday – the date flagged by Treasury for when it will run out of the ability to borrow – or else stocks will tank, interest rates will spike and markets will presumably force quick action in Washington, as they did with the Wall Street bailout in 2008.

A default won’t occur at the stroke of midnight Thursday — given the timing of when payments to creditors are due and how much cash will still be on hand, there is some time before the Treasury is short of funds.

But that will be of little comfort if there is no deal in sight.

“Is Thursday a hard and fast date? No, but the Oct. 17th threshold is psychologically important if there’s no debt ceiling resolution,” said Joseph Quinlan, chief market strategist at U.S. Trust.