For years the baleful shade of Enoch Powell silenced debate about immigration numbers, however rational. Playing the numbers game, as it was called, was always associated with the even more shameful misdemeanour of playing the race card.

As recently as November 2003, David Blunkett as home secretary blithely announced that he could not see the need for a limit on immigrants, nor did he think there was a maximum number of people that could be housed in this country.

This astonishingly silly comment passed almost without protest; it was expressing the unthinking orthodoxy of the day. It was fortunate perhaps that Blunkett and the government believed that numbers didn’t matter, since they hadn’t the slightest idea what the numbers were.

The director of enforcement and removals at the Immigration and Nationality Directorate admitted last year that he had not “the faintest idea” how many illegal immigrants were living here. Not only has the government lost control of this country’s boundaries; until recently it didn’t think that mattered.

How quickly things change in politics. Now even the most right-on Labour figures are playing the numbers game, with the race card up their sleeves. Last month Margaret “Enver” Hodge appeared to be doing just that with her announcement that indigenous people in her constituency of Barking felt justly aggrieved that they could not get council housing, while recent immigrants could. They had indeed “a legitimate sense of entitlement” that should not be overridden by new immigrants. The wind was clearly changing.

Sure enough, last week numbers became mentionable again, officially. Ruth Kelly, the minister for communities and local government, issued a startling report by the Commission on Integration and Cohesion. Integration indeed. Until recently integration was a dirty word, almost as sinister as assimilation.

This report announced findings that must be startling to anyone who has tried hard to toe the multi-culti line. It says that black and Asian Britons - nearly half of them - think we have let in too many immigrants.

Almost 70% of everyone questioned by a Mori poll for the commission thought so, including 47% of Asian and 45% of black respondents. The poll also showed that 56% of respondents believed some groups - mainly immigrants, asylum seekers and refugees - received unfair priority in the allocation of housing, health services and education. Respondents were “very sensitive about freeloading by other groups”. At the same time only 36% believe immigration is good for the economy.

It is hard to know what to make of the idiocy of this government, discovering so late in the day the consequences of its wilfully ignorant and undemocratic immigration policies. Nevertheless one should be thankful for small blessings. There are a few. For one thing, because it’s now official that so many ethnic minority Britons are worried about immigration, the race card has in effect been torn up and thrown away. One can hardly accuse ethnic minorities of playing it.

Another blessing is that multiculturalism has suddenly and rather sneakily been dumped. Late in the day ministers are discovering what should have been blindingly obvious. The dogma of multiculturalism has made immigration and race relations much more painful and difficult than they need have been. The social policies based on it have kept people in ghettos and bred mistrust and suspicion.

So it’s as you were, then, with multiculturalism. Now at long last we have integration and cohesion. Let’s hope it’s not too late to undo some of the damage.

Kelly’s report makes some sensible suggestions, none the worse for being ridiculous U-turns. The policy of providing masses of translators and translations for countless languages is to be dumped. It has meant that newcomers are not obliged to learn English, and frequently don’t, which means they are unable to integrate even if they wanted to; they can live here deaf and dumb to the rest of us. Good riddance to it.

However, changes such as this, no matter how sensible, fail to address the central question of numbers. It ought always to have been self-evident that numbers matter; to think otherwise is to believe that a raft will never sink no matter how many people clamber onto it.

Of course immigration is to be welcomed, or at least tolerated. Of course immigrants have done great things for this country. Of course there is a moral argument for rich people in favour of taking in poorer foreigners. And of course asylum seekers deserve asylum. All the same, this small and populous country cannot possibly accept the many millions who would like to come here.

This government, or its successor, ought to be bold enough to consider openly what might be the optimum number of people living here - or at least the number beyond which more would be intolerable. Some think we have already reached it, to judge from letters to this paper last week about housing. Most do not, but some day we certainly will, unless immigration is brought under civilised and thoughtful control.

No one would wish to turn away genuine asylum seekers. No one can turn away migrants from the European Union, whether we wish to or not. The result is that we already have far more prospective immigrants than we could hope to accommodate.

The number of genuine asylum seekers is limitless and the number of EU migrants, with incontestable rights to settle here, is as good as limitless. Surely it follows that the group that morally or legally has less right to come here is therefore the immigrants who are neither EU nationals nor spouses of Britons. So, no immigrants except asylum seekers and Europeans?

There is nothing racist about this suggestion; plenty of Europeans, and most asylum seekers, are of non-European ethnic antecedents. There are Moroccan Frenchwomen or Indonesian Dutchmen; Europe has become a melting pot. Certain exceptions could be made, as ever, for immigrants who would bring exceptional wealth or skills with them. It is, at the very least, time for the government to talk openly and fearlessly about numbers.

minette.marrin@sunday-times.co.uk

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