Sajid Javid nailed it.  “Britain isn’t building enough new homes,” he wrote on this site last December.  As he knows well enough, the obstacles to doing so are formidable.  We are a not-very-big country with a very-compex-indeed planning system.  Top that up with older people who don’t want to move out of their homes, and younger people who live in a different way to them – marrying less, splitting up more (see today’s Mail on Sunday), coping singly – and demand will outstrip supply, even when immigration from the EU falls post-Brexit.

Add English rural nostalgia to the mix, and constraints tighten further.  The self-sacrificing workof Nick Boles and other Ministers; the forceful case made by think-tanks such as Policy Exchange, the IEA and Civitas, and people’s experience of seeing their grown-up children unable to afford to buy a home have shifted public opinion quite a bit, perhaps a lot.

But the bottom line is that Nimbyism is not dead, but sleeping.  A proposal to build in another neighbourhood’s back yard is a triumph of social justice.  A plan to do the same in one’s own is an affront to local democracy.  Conservative MPs take fright when enraged constituents come pounding on their door.  No wonder the last Tory manifesto said in a section headline that “we will protect the green belt”.

Furthermore, this mix of limited supply and social change is stifling home ownership.  This is now at its lowest level since before the Thatcher home ownership revolution – falling from a peak of 71 per cent in 2003 to 64 per cent in 2011, from which it has not moved.  But 86 per cent of Brits want to own their own home.  That so many cannot afford to do so is what Theresa May calls a “burning injustice” – and, incidentally, bad for the Conservative Party too.

Her Government is committed to getting a million homes built over the next five years, and the Coalition got the numbers moving the right way.  None the less, Ministers are not on course to realise their aim.  As Daniel Bentley pointed out on this site yesterday, there were about 160,000 completions last year.  That is well below the 230,000 homes a year needed just to keep up with projected household formation.

To the Communities Secretary falls the task of squaring this obdurate circle.  He must somehow raise the housebuilding numbers still further while not frightening the backbench horses at the same time – and simultaneously ensure that home ownership moves back in the right direction.  George Osborne gave him some help on the latter front before departing in the form of the tax squeeze on buy to let.

Javid is expected to publish his Housing White Paper on Tuesday.  We know from briefings and leaks, not least in today’s papers, what is likely to be in it.  Under the Coalition, Osborne specialised in demand-led measures such as boosting Right to Buy and introducing the Help to Buy schemes.  The Communities Secretary will concentrate instead on furthering the supply-side changes drive through by Eric Pickles and Greg Clark.

He will doubtless announce another push on building on government-owned land.  He will presumably try to tighten up the “use it or lose it provisions” for developers and others.  And he will attempt to squeeze all he can out of brownfield.  But the green belt remains key to his plans – and that piece for this site suggested how bits of it can be built on with the manifesto pledge remaining unbreached.

Javid referred to Birmingham – “where the council’s local development plan calls for the re-designation of a small area of green belt land”.  He was referring to the proposed building of some 6000 homes in Sutton Coldfield – the cause of Andrew Mitchell’s attack on him in the Mail on Sunday today.  The example shows that some local councils will turn to green belt if they are required to build, and feel they have no alternative open to them.

The White Paper is unlikely to issue anything so crude as targets.  But by one means or another it will find ways of ratcheting up the pressure on local authorities to build; the recently-passed Neighbourhood Planning Bill did so over the requirement on them to have an adopted local plan.  And if councils cannot find other places to build, they will duly look to the green belt.

A breach of the manifesto?  Not so, Ministers will say.  There will be no new loosening of the green belt, merely use of it in what Ministers are calling “exceptional circumstances”.  And have another look at that manifesto, which had more to offer than a headline. The section below it said that “we will ensure that brownfield land is used as much as possible for new development” [our italics].

Furthermore, the Government will not need secondary legislation – or even statutory instruments – to effect the main changes it wants.  This will have helped Javid’s radicalism and May’s caution reach an accomodation.  The Prime Minister knows how strongly voters feel about development from her own experience in Maidenhead.  But her commitment during her leadership campaign was unambiguous: “we need to do far more to get more houses built”.

You may well not approve of this circuitious route to more housing.  Or you may do so, and still believe that the odds are against the Communities Secretary’s stealth route to more homes – that he will not be able to squeeze a housing quart out of the system’s pint pot.  If so, there are only two consistent alternatives to what he wants to attempt.  One implies less state action, the other even more.

That first is simply to get government out of planning altogether and tear up the Green Belt entirely.  The consequences for the countryside and environment aside, this would not be politically acceptable in Britain for the reasons already outlined.  The second is to have a reforming rethink, for the 2020 manifesto, of how we are to build the houses we need – which would necessarily involve not removing the Green Belt, but recasting it.

One might imagine from some of the campaigning to protect it that the belt is the same as areas of outstanding natural beauty.  This is not so.  The land that makes it up is of variable quality.  It ought not to be beyond the wit of man to strike a grand bargain. Some of the less “glorious” parts of it – to use Mitchell’s word – would be turned over to new housing.  The protection of the more attractive bits would be stepped up.

The state would buy the land.  Local Government would build homes for sale, as we proposed in the ConservativeHome Manifesto.(along with housing associations and other social landlords).  National government would ensure that the vital element missing in so much housing development was provided: cash for better roads, social services, schools and amenities.  It would be a natural extension of Philip Hammond’s infrastructure schemes.

What would stop the state coming back for more green belt later?  Other than public opinion, the answer lies in social trends.  The baby boomer generation will die off.  Automation is likely to cut the demand for low-skill immigration.  The need for new housing is likely to be a medium-term expedient, not a long-term requirement.  In the meantime, we would have larger garden towns and new garden villages.

In the aftermath of the Second World War, Macmillan hit his target of building 300,000 houses a year.  Now Javid must strain to reach his own.  There are big differences between then and now ()not least that a big slice of the former’s homes were council houses for rent).  But in one sense there is a similarity – or should be.  As Andrew Gimson wrote, in telling the tale of that post-war national effort, Macmillan got unambiguous backing from Churchill, and from the party more widely.  We hope Javid gets the same.