When the theory was first put forward that the modern world faces a clash of civilisations, it raised a hot debate, with politically correct individuals denouncing it as encouraging intolerance.

When events proved that many modern conflicts had at their root a conflict between people holding to a way of life that could not be reconciled with that of their neighbours, in a globalised world which made us all neighbours, some apologists went as far as to blame individual human behaviour rather than the civilisation from which they come.

Let us not delude ourselves. Civilisation can only manifest itself through human behaviour. It is not an abstract concept.

The case of the sentence of imprisonment of an English teacher in Sudan for accepting the suggestion of an innocent pupil to give a teddy bear his favourite name, Muhammed, is a classic example of the clash of civilisations that the world is facing. It is a case where the incomprehension of a harmless attitude on one side has led to a popular cry for the execution of a devoted, and well-meaning, innocent person. The pardon granted by the Sudanese president is mot welcome, but it does not mean that a clash of civilisations, which must be tackled at its root, does not exist.

Let us not dismiss, attenuate or try to explain away these developments as an isolated aberration on the part of a few hotheads. The core element is a judgment by learned judges applying the law of a land based on deeply held religious beliefs, central to the civilisation of the country.

The clash of civilisations emerges from the fact that intelligent people with two different cultures looked on the same act with widely different values.

We have a cuddly toy on one side, but a wild animal on the other. Giving a name, especially a favourite one, to a toy is considered a compliment on one side but an insult to the other. No sane Christian would object to giving the name Emanuel to a toy on the grounds that it is also the name of the founder of Christianity. Yet, in the eyes of the learned Sudanese judges the name Muhammed is only identified with the founder of Islam.

The fact that there are millions of people, not all of exemplary character, bearing that name is beside the point. It is true that the view of these judges does not seem to be upheld by prominent Muslims in the UK, who are more familiar with the civilisation in which they are living. On the other hand, the crowd in Khartoum is baying for blood, and there is no evidence that leaders of the Sudanese society are restraining it.

This is not a call for Christians to draw their swords and engage in battle with Muslim scimitars. I have no sympathy for bloody crusades or jihad. What I plead for is an honest evaluation of a dangerous situation which can only get worse if protagonists in the defence of a civilisation, especially politicians, religious leaders, academics, and opinion writers ignore it.