The Archbishop's primary role, one assumes, is to care for the souls of his own dwindling flock. Instead, poor Dr Williams gets his surplice in a twist, proposing with the garbled logic of which only a true academic is capable that part of the answer to the dual allegiance felt by British Muslims might be to recognise certain aspects of sharia law. It is a relief to learn that the Archbishop is not recommending public executions in Brick Lane or the cutting off of thieves' hands in Burnley. But his proposal is still intellectually contemptible and socially dangerous. It is a counsel of despair masquerading as feel-good ecumenism.
Yes, many British Muslims have dual loyalties. In the era of globalisation and population mobility, this is common enough, as identities pile up within individuals. British Catholics have long confronted (successfully) the question of distinct allegiance to Crown and to Rome. Likewise, British Jews are perfectly capable of identifying passionately with the state of Israel but being, first and foremost, citizens of this country. Our islands teem with new Britons who have complex emotions about their new home and where they have come from.
At a time of doubt, all the more reason for clear guard-rails, at least where public obligation is concerned. The cement of our ever more pluralist, diverse society is the law: our equality under the law is the most meaningful form of equality that we have. Indeed, the law is the best guarantee that ethnic minorities and immigrant communities have of fair treatment.
It is spectacularly wrong headed of Dr Williams to argue for more fragmentation - customised legal systems for different groups - rather than the legal uniformity that allows religious diversity to flourish and acts as a firewall against discrimination.
The Archbishop advances the jurisprudence of appeasement, an example of liberalism defeating itself by kowtowing to fundamentalism. The very last thing this country needs to add to its many stresses and dysfunctions is the establishment of legal ghettoes.