The British government is concerned about food security because of the recent escalation of prices caused by the apparent shortage of supply in the global market. But while it makes sense to increase agricultural outputs responsibly, this cannot be justified on the grounds of security. The term “security” is an emotive one, conjuring up images of wartime food shortages caused by German U-boats. But it is inconceivable, in today’s world, that such an emergency would re-occur.

Today Britain is about 60 per cent self-sufficient in food production. Much of the remaining 40 per cent is made up of crops that could not be grown here for climatic reasons. Until 1846 Britain was virtually self-sufficient, thanks to protectionist barriers that restricted imports. But these were slashed by the government of Sir Robert Peel when he repealed the Corn Laws, thereby allowing cheap food into the country to feed the rapidly expanding urban population. Self-sufficiency declined steadily – interrupted briefly by the blockades of the first and second world wars – and was less than 40 per cent by 1939. After the war agricultural output rose steadily, and British farmers increased their market share from 40 per cent to a peak of 70 per cent in the 1970s. This was achieved behind protectionist barriers, first national and then European. When Britain joined the European Economic Community its farmers were encouraged to produce large surpluses, which had to be dumped on the world’s markets. The European Union then imposed production restraints, taking land out of crop production. Consequently British self-sufficiency declined to 60 per cent today – still a high figure in historic terms.