So now it has happened, entirely as predicted in this column years ago. With the super-high-density city proving unpopular - as well as horrendously expensive and as bulky and slow as a juggernaut to steer through the planning process - we are to revert to nibbling away at the Green Belt. Thus 'Protecting the countryside' retreats from an inviolable principle to an empty slogan, backed up by newspapers full of photographs of outraged or devastated or distraught country dwellers gazing out for the last time over green fields they thought they owned forever.
The scene is affecting, so much so that it would deserve a prize for tragedy, were it not for the fact that it deserves an even better prize for farce. Why? Because the high-density, sub-rural 'Million new homes to be crammed into the South East' about which there was such a furore last week, represents the absolute minimum of greenfield land and the absolute maximum of transplanted urban density. In all but name these houses will be urban houses, high-density, low-rise 'millennium' dwellings designed to 'wean people away from their cars' - an absurd ambition for any rural area - and pig-pile them into dependence on a public transport network that does not yet exist.
The media takes an ambivalent view of all this. 'Key workers' must, of course, be found homes, but on the other hand crocodile tears must be shed over the 'fears' of environmental groups about new runways, airports and other evidence of economic life in addition to housing. It is a commentary on our strange value system that building houses in the Green Belt is seen as an 'intrusive'activity in the non-urban South East, where there is room for at least three million dwellings at densities as low as the Australian outback, yet one that would be 'welcomed' anywhere in Greater London where there is scarcely room to run a bus.
The reason for this anomaly is a mixture of abstract classification and political spin. Hypnotised by the glitz of the Urban Task Force celebrity floor show, today's planners resolutely refuse to pay any attention to the enormously increased quantity of surplus agricultural land available for low-density development that has come onto the market as a result of the globalisation of the food industry. For them, there is still only brownfield land, Green Belt land and 'countryside', the last an ill-defined but hotly defended paradise that only a Genghis Kahn (or a farmer), would be so insensitive as to consider selling off for such an unexotic purpose as development.
It is the anomalous state of the countryside - sacrosanct but also redundant and (thus far) Brussels-wise administratively unclaimed - that focuses attention on the wholly inadequate development prospects offered by patchy brownfields and marginal Green Belts, however thin and wherever they may be. Conversely it is the lack of contact between politicians and land use issues - without foot-and-mouth disease approximately nil - that shows us the hiatus between agriculture and environmental stewardship will not last forever.
In any case, bidders other than housebuilders are not so reticent.
The burgeoning nature conservancy movement has long been eager to take over the grants and the mystique that were for many years the source of farming wealth.
And even thinner bones are being squabbled over.
The Council for British Archaeology has made a pitch for 'entirely non-renewable' resources in the shape of unexcavated prehistoric sites hitherto 'lost to posterity under the plough', but now, 'within the current rethink of agri-environment funding', enjoying an important opportunity. An opportunity, perhaps, to insert low-density rural development with the countryside, the most bountiful, plentiful and suitable source of building land.