Iain Duncan Smith said yesterday that Westminster politicians of all parties should get out of the House of Commons more often and go into the inner city areas where there is so much violence, crime and social disorder. This is where children have been known to kill one another for a mobile phone.

Duncan Smith said that part of the problem is that in the inner cities it is not uncommon for drug addiction to persist over three generations: not just the youth, but their parents and grandparents. Imagine grandpa too as a junkie. Duncan Smith also said that the inner city is not so much a geographical area as a state of mind.

And he is right. The cause of the social decay is the fact that, for 40 years, the metropolitan elite, the permissive "reformers" and the trendy thinkers in powerful political positions have undermined and destroyed our institutions. The institutions are those most precious parts of society which are above politics: the family, schools, the law and the Church. They are what, for the greater part of the last century, provided a decent standard of social cohesion in our country.

The basic unity of our society is the family. But the family has been undermined by economic disincentives which have made it financially more rewarding for couples to co-habit - what in downtown Leeds where I grew up we used to call "living over the brush" - than to marry. Single parenthood and the cult of the absent father has also been encouraged in this way.

Homosexuality has been promoted so that it is now regarded as the moral equivalent of marriage. I think it right that the Homosexual Reform Bill was passed back in 1967. This meant that homosexuals no longer had to live in fear of prosecution. But there is the world of difference between tolerating an aberration and actively encouraging it, as if it were the moral equivalent of marriage.

Schools have been undermined, first through the almost total abandonment of any discipline. Scores of teachers have said to me: "If I had my time over again, I'd never go in for teaching. It's like a jungle in the classrooms; and we have no sanctions against the pupils' lawless and violent behaviour."

At the same time standards have plummeted. Never mind the Government's insistence that, on the contrary, they are rising all the time: just compare an O-level or an A-level exam paper with the dumbed-down illiteracy which constitutes the curriculum today. They have sold off the playing fields and campaigned against competitive sports - and now they complain of an obesity epidemic.

The Church used to provide a standard by teaching the moral law and the Ten Commandments. But now it has thrown away our English Bible and Prayer Book in favour of trashy modern prayers. And the Church is now presided over by Archbishop Williams, who recommends that our youngsters should read the blasphemous novels of the anti-Christian Philip Pullman. Jesus said: "Suffer the little children."

As a result of the wilful destruction of our institutions, the children's suffering is more pitiable than ever - especially in the inner cities.

* Peter Mullen is Rector of St Michael's, Cornhill, in the City of London, and Chaplain to the Stock Exchange.