David Davis obliged last week with an article in The Daily Telegraph that began by promising not to indulge in knee-jerk responses. When politicians say that we all know to look straight at their trouser-legs, where the old patellar reflex will surely follow. Davis's knee did not disappoint.
The time has come, he declared, to turn back the clock on multiculturalism. We have made the mistake of "allowing people of different cultures to settle without expecting them to integrate", where instead "we should not flinch from demanding ... tolerance and respect for the British way of life."
The "wake-up call" of 7 July, he said, showed us that we must "ask searching questions" about what is happening inside Muslim communities. For too long we have been encouraging distinctive identities without promoting common values, and the time has now come to build a single nation in which everyone believes.
It is not hard to tell, in the midst of a leadership contest, for whom this particular jerk of the knee is intended, but it also serves as a measure of how far out of touch the front-runner and his audience are. If the attacks of 7 July were a wake-up call then Davis must have slept through it, because one glance at the death list from that day would have told him that multiculturalism is not a choice. It is a fact.
The victims were Vietnamese and Scottish, Bangladeshi and Mauritian, Jewish and Hindu, Polish and Nigerian, and much, much more besides. David Davis may live in a world of "we" and "them" (and how, I wonder, does he divide the two?), but the lifeblood of the capital city, peopling its Tube trains and buses and suffering the brutality of its enemies, is not segregated in that way.
Yet apparently "we" should not flinch from telling "them" that they must "integrate". If Muslims ran their mosques and chose their imams and instructed their young people as "we" want them to, and if they signed up to that "single nation in which everyone believes", then apparently "their" bombers might not pose such a threat.
These ideas would be quaint if they weren't so wrongheaded, and they suggest that Davis wants to take us back into the world before the Stephen Lawrence case.
Only a few days after the death of Anthony Walker in Liverpool it may seem perverse to make the claim, but this country has come a long way since the Lawrence murder, and many of the ideas associated with that word multiculturalism have played their parts.
One measure of the change is the simple fact that we all knew about the Walker killing within 24 hours, whereas it took four years of campaigning and litigation by his parents before Stephen Lawrence's death became the stuff of front-page headlines. Newspaper editors have changed, and so have the priorities and concerns of their readers.
Back in 1993 the police logged the Lawrence death as a racial crime, but that meant nothing more than adding it to the statistics. And the only sense in which the racial aspect of the murder influenced the investigation was that police officers of all ranks treated black people as if they were the problem. Was this person an activist? Could that person be trusted? Were they all going to go off and start a riot?
Perhaps the most incredible aspect of an extraordinary investigation was that, when eventually they got a group of five likely suspects in their sights, the detectives never once, in months of fruitless investigation, made an effort to find out whether those suspects had in the past expressed racist attitudes or displayed racist behaviour.
Such mistakes are extremely unlikely to be repeated today.
And if the police have made progress, so has the public. In 1993 it was common to see British people shrug off the racism on their doorstep with the remark that it was worse in France or Germany. The "bad apple" theory prevailed, under which British people were held to be overwhelmingly nice and it was just a few ugly psychos who were the problem.
By my reckoning, that is now a minority view. Look at the response to the London bombings: there is a widespread alertness to the problems that can flow from routinely stopping and searching young Asian men. Back in 1993, to express such concerns was to define yourself as a race agitator or a civil liberties activist, and to be dismissed as marginal; now the anxiety is in the mainstream and neither police chiefs nor government ministers can afford to ignore it.
Nor is this, as the dunderheads suggest, a matter of political correctness. It merely recognises the likelihood that if young men in a group of communities that are already in difficulties are placed under routine pressure by police officers, trouble will follow.
To say there has been progress, of course, is not to say that racism has gone away or even declined. It has not gone from the streets, where Anthony Walker died and so many Muslims are being abused and attacked, or from the police, where we saw it in BBC1's The Secret Policeman. Nor has society at large shaken off its reflexes. Ask yourself, would Anthony Walker have commanded quite so much sympathy or attention if he had not been an exemplary young man - if he had had, for example, a drugs conviction? Is the bar higher especially high for black victims of crime?
Yet the centre of gravity in the race argument has moved since 1993, and that is largely because society has learned to respect difference, which David Davis wants it to stop doing.
The Macpherson Report into the Lawrence case contained a telling passage in which the police family liaison officers assigned to the Lawrences in 1993 were taken to task for the casualness, suspicion and critical attitude they showed towards this grieving black couple.
"The family of Stephen Lawrence had to be taken as they were found, and chose to behave," declared the report. "They were entitled to demand to be dealt with as they were and according to their own needs."
That some Muslims (of widely varying ethnic backgrounds) have planted some bombs does not give anybody in this country the right to impose their values on the rest, any more than the death of Anthony Walker entitles anyone to rearrange the lives of all the people of Huyton.
More than that, this imposition of values will not happen. David Davis cannot integrate us or create a British monoculture. If we obey the law - and we are not short of laws - and if we show a modicum of respect for others, then whoever we are we must be allowed to practise the culture, religion or lifestyle of our choosing.
In Sir William Macpherson's amiable terms, we are all entitled to be taken as we are found, and as we choose to behave.
Brian Cathcart is the author of 'The Case of Stephen Lawrence'Reuse content