I thought Theresa May would survive – now I’m not sure. Sajid Javid could be PM by the end of the year

The home secretary has been busy making himself popular just as Tory MPs are beginning to despair of the prime minister

Sajid Javid has a new special adviser. The last time I commented on a cabinet minister hiring a new special adviser it was Theresa May, the home secretary, and six weeks later she was prime minister. She hired Joey Jones from Sky News: he didn’t follow her into Downing Street but his appointment was a statement of intent.

Until this week, I assumed May would be the prime minister who took us out of the EU in March. Her strategy of delay, procrastination and attrition isn’t pretty, and risks cutting the Brexit deadline fine, but it seemed to be working. This week, it didn’t.

Faced with defeat on the provision in the EU (Withdrawal) Bill to give parliament a say over the Brexit terms, she postponed the vote in the Commons. So far, so Fabian. (Fabius Maximus, the Delayer, after whom the Fabian Society is named, defeated Hannibal by waiting, and waiting, for the right moment to strike.) Then she gave Dominic Grieve, leader of the soft Brexit faction of Conservative MPs, the impression that she had agreed a compromise form of words.

By the time the text was published two hours later, though, David Davis, the Brexit secretary, had threatened to resign again (at least the second time this week), and the wording had been diluted. Trying to split the difference between the two sides of the party is only possible if both sides think she an honest broker. Now neither side trusts her.

No one knows what will happen when the bill comes back to the Commons, probably on Wednesday after it goes to the Lords on Monday. If Julian Smith, the chief whip, decides he can’t be sure of winning, the vote could be postponed again.

Tory MPs have been saying for months that this can’t go on, and yet, every month, it has. Now the prime minister is going to try to secure cabinet agreement at a two-day meeting at Chequers, probably on 5 and 6 July. If she succeeds, and if Davis is still Brexit secretary, there will be a white paper setting out the policy and a vote on post-Brexit customs arrangements in the Trade Bill before the summer break.

Until this week, I thought the law of mutual weakness would keep Theresa May in post. Neither wing of the party wants to get rid of her for fear of getting one of the other side as leader. Into this vacuum Sajid Javid has stepped, now backed up with three political advisers (the usual limit is two); a reluctant Remainer whose first act as a member of the Brexit inner cabinet was to side with Davis, Boris Johnson and Michael Gove on the customs question.

This week Javid lifted the cap on immigration for NHS doctors and nurses, and today he helped to change government policy to allow a boy in Northern Ireland to import cannabis oil to treat a life-threatening condition. May’s distraction by Brexit means he can make popular policy changes and take the credit for them.

He has only been at the Home Office for six weeks and already he has ended the “hostile environment” policy on illegal immigration that gave us the Windrush scandal, made his peace with the Police Federation, the toughest trade union after the British Medical Association, and promised to deliver a law against upskirting after a maverick Tory MP blocked it.

I have given up trying to guess how the Brexit brink-and-bluff is going to play out. I had assumed the Commons would force the government to go for a soft Brexit rather than a hard one, with “soft” meaning a customs union with the EU and “hard” a Canada-style trade deal.

But the longer this goes on, and especially if Dominic Grieve’s amendment gives the EU side more of an incentive to drive a hard bargain, the more the nightmare choice between Brexino (Brexit In Name Only) and crashing out without a deal seems possible.

I can only report that the mood among Tory MPs has changed. One minister told me the best thing would be to “blow up the whole thing” and cancel Brexit. There are many backbenchers who have not yet voted against the government but who agree with those who have, either on a customs union or on full membership of the EU single market.

The situation looks increasingly unstable and, if the Tory party is looking for a prime minister with a middle position on Brexit but who can make decisions, Javid is available. In a survey by Conservative Home last month, party members – who would make the final choice of leader – put Javid in third place behind Jacob Rees-Mogg, who probably wouldn’t get enough support from MPs to make it on to the ballot, and Michael Gove.

Fortunes rise and fall fast, but it now seems possible Javid could be prime minister by the end of the year.