The logic of most Conservative MPs as they ponder their party’s and country’s future begins as follows.  To bring down Theresa May and hold a leadership election to replace her, amidst the great national event that is Britain’s EU negotiation, would risk not only a successful outcome but a general election.  And since the latter might result in a Corbyn Government, the Prime Minister must be left in place – not, to be sure, in order to lead the Party into the general election due in 2022, but as a caretaker until that Brexit negotiation is over.  Then she can stand down in an orderly way, that leadership poll can follow, and a new Tory Prime Minister can enter Downing Street, just in time for the run-up to 2022.  Perhaps that Prime Minister does not now sit in Cabinet at all – which is no bad thing, since many of them, like Party activists, are underwhelmed by its members.

This view is a persuasive one.  But it is founded on the assumption that the Conservative Party must be led for the moment by a Prime Minister in whom both they and Party members have no real confidence.  For to change, Theresa May herself must either publicly accept that she is now only a caretaker, or else prove that the assumptions on which their view is founded are wrong, and that she can reassemble herself and her government in such a way as to lead the Tories to an election victory next time round.

When this Parliament began, it seemed that the Prime Minister believed that her premiership would finish before 2022 (or whenever that election is held).  She told Conservative MPs that she would stay on as leader for only “as long as you want me”.  Then, during a visit to Japan, she seemed to change her mind, saying that she “not a quitter” and is “in this for the long term”.

It follows not only that she must explain today why her Party should enable her to do so, but why both she and it are better suited to run Britain than Jeremy Corbyn.  That the Opposition leader came less close to winning the election than she did does not provide an answer.  For his own party’s conference last week confirmed that he has a coherent view of how Britain to be governed, and the Conservative one so far has not offered an alternative.  In more than one sense, Corbyn has momentum.

The origins of May’s difficulties lie not in the election that she didn’t win last summer, but one that she did the year before.  Andrea Leadsom’s withdrawal from the Tory leadership contest led to the Prime Minister winning it outright, and therefore entering Number Ten without her ideas having been tested by party members or probed during a poll by the media.  That mattered less when the Conservatives had a Commons majority.

Now, however, they don’t have one – and the architect of many of those ideas, Nick Timothy, no longer works in Downing Street.  His replacements are operationally more deft, but ideologically less committed, and the difference has been felt in Manchester this week.  The Conservative conference programme maintains his slogan intact on its cover – “a country that works for everyone” – but the conference itself to date has not explained how this noble aim is to be delivered.

Timothy had an answer: through “the good that government can do” – a sensational repudiation of Margaret Thatcher and her intellectual inheritance, manifested in a range of policies from energy price caps through more council houses to workers on boards to “a proper industrial strategy”.  Now, however, May not only has no majority to deliver most of this programme (for better or worse), but the context in which she must work has been radically changed.  Corbyn may not be in office, but his ideas are in power, or at least making the running.  He has his own interpretation of the good that government can do, and it is making waves among younger voters.  The case for capitalism no longer commands consensus, as it did during the Thatcher and Blair periods of government.  The 1970s were a long time ago.  And Venzuela is a long way away.

The Prime Minister told the ConservativeHome party on Sunday evening that the Tories must once again make the case for the market economy (and by extension for the free society).  What isn’t clear as she prepares to make her speech today is whether “the good that government can do” is still at heart of her programme, and if so how making the argument that she described on Sunday is consistent with it.  Other Ministers are beginning to fill the gap: Philip Hammond and Boris Johnson are scarcely the best of friends, but both in their different ways have had a go in their conference speeches.

Now it is May’s turn.  If she is to have any chance whatsoever of contesting the next election as Conservative leader, she must begin to do something today that is far more important. The sum of what this conference has offered so far is a series of spodadic announcements.  To follow the Foreign Secretary in quoting Winston Churchill, it has been a pudding with no theme.  The shadow of Timothy’s ideas linger on without the substance.  No wonder the conference has been flat, bewildered and underwhelming, as we wrote yesterday.  Today, May should set out why the system that Corbyn opposes is worth keeping, but reforming.  And she should go on to explain how it will deliver, under a Conservative Government, for those younger voters who are losing faith in it.  The key to that isn’t more subsidies for student fees; it’s giving them a stake in the system.

Which means boosting the supply of homes rather than demand for them through help-to-buy.  Which also means identifying herself with the drive for more housing and higher ownership.  Which means, too, spelling out how better technical education can be offered to the two-thirds of young people who don’t go to university all, so that their work prospects and earning power can be boosted.  Which means developing plans for savings throughout the life cycle as the age of the defined benefit pension recedes.

Neither the Prime Minister nor her government will survive if Brexit is not delivered coherently – deal or no deal.  More importantly by far, neither will deserve to if they can’t explain why reforming the system will deliver more gains for workers and familes than tearing it up.  There is a lot more at stake in Tory MPs’ decision to keep or junk May than their own electoral prospects.