What Mr Alford does not say is that it is also possible to manufacture bombs from the only other high-nitrogen fertiliser available in the world: urea. The US press claims that urea was used in the recent World Trade Center bomb in New York. It is reported that the London bombs were manufactured from CAN and then brought over from Ireland.
We are therefore faced with the unhappy fact that all the main nitrogen fertilisers - the use of which has allowed food production to keep pace with increasing world population - can be used as components for bombs. Attempts over many years to alter their chemical composition to prevent this have failed.
Greater use should be made of recycled organic nutrient sources, but the world's population cannot survive without use of fertiliser, made from nitrogen extracted from the air, which speeds the natural nitrogen cycle. To ban them in the UK would not prevent terrorists getting hold of them. The only way forward is for us all to be as alert and security-minded as possible so as not to make life easy for evil people.