It’s been true for a while that the Conservative party has become fundamentally ungovernable, its warring factions so far apart it’s all but impossible to have them marching in the same direction, at least when it comes to Europe. It’s a condition that afflicted the Tories under Theresa May’s predecessors, spelling doom for David Cameron, John Major and Margaret Thatcher. But today Britain has to face a condition that is new: not only are the Conservatives ungovernable but, under the Tories, the country itself is ungoverned. Functionally, the United Kingdom currently lacks a government.

Consider that today Tory MPs will have a free vote not on one of the traditional issues of conscience – relating, say, to religion or personal morality – but on a question that is among the most significant to have confronted the UK in peacetime: namely, whether to crash out of the European Union in 16 days with no deal. By refusing to compel its MPs to vote one way or the other, May is saying that, even on “an issue of grave importance”, to use her own words, her administration has no official view. As the political scientist Prof Philip Cowley puts it: “On one of the most fundamental questions about Britain’s future, the government will be shrugging its shoulders and saying: ‘whatever’.”

That was the real meaning of May’s address to MPs on Tuesday night, after her withdrawal agreement was rejected for the second time by a three-figure margin. In effect, she was telling the Commons that she and her government had failed to solve what Danny Dyer famously – and rightly – called the “mad riddle” of Brexit, and that she was dumping the entire mess into the lap of parliament. Now it will be up to backbench MPs, led by Labour’s Yvette Cooper and the Tories’ Nick Boles, to eke out some kind of solution. In the centuries-long contest fought in these islands over where power lies – with parliament or the executive – May’s retreat marked a significant moment, a shift from the latter to the former.

It’s worth stressing that today’s vote is not just free for Tory backbenchers, but for ministers too, including the most senior ones. May has, in effect, admitted that if she instructed her colleagues to rule out no deal – or, indeed, to refuse to rule it out – many would disobey her instruction. The former deputy prime minister Michael Heseltine was right to tell Radio 4’s Today programme this morning that: “They’ve not only lost control of the House, they’ve lost control of the cabinet.”

For proof of this absence of government, look no further than today’s spring statement by the chancellor. Normally this would be a major news event, dominating the political cycle for the entire week. Instead, it’s been downgraded to little more than a B-movie before the main feature of the no-deal vote. Indeed, its chief purpose is Brexit-related, with Philip Hammond showing off all the shiny spending he would be able to commit to other things, if only he didn’t have to hold it back to soften the blow of a potential no-deal exit. His is the role of a TV gameshow host, tantalising the contestant by showing them what they could have won.

Which means that, because of Brexit, that money cannot be immediately allocated where it’s needed – to end austerity; to fund schools so that cash-strapped headteachers don’t have to work an extra shift as cleaners just to make ends meet; to fund police officers so local forces have a chance to tackle rising knife crime; to perform, in other words, the basic tasks of government.

This is work that is going undone, by a Tory administration that has been wholly consumed by Brexit for nearly three years and that now admits it cannot lead even on that. Forget Brexit in name only. Right now we are a country saddled with a government in name only.

• Jonathan Freedland is a Guardian columnist