At the end of the first world war Marshal Foch famously observed that the Versailles treaty would bring not peace but “an armistice for 20 years”. Wednesday night’s last-gasp deal in the US Senate to end the government shutdown and avert collision with the debt ceiling has a similar flavour.

While the deal might, of course, mark a genuine reset in relations between the White House and Congress, it might also – as with Versailles – be little more than a temporary interruption in hostilities. At least we shall not have long to find out. The armistice this time will run not for 20 years – but for less than 20 weeks.

The first reaction to the deal is, inevitably, one of relief. It eases for now rising market neurosis over the threat posed by the stand-off to the full faith and credit of the United States. The White House emerges from the fray with its red lines intact. President Barack Obama has stuck to his refusal to bargain over any increase in the debt ceiling. There has been no quid pro quo on the budget. Faced with collapsing ratings in the opinion polls, the Republicans have been forced to blink.