Britain published its first food security assessment on Monday, an admirable and balanced attempt to monitor a complex issue. Predictably, it was met with a simplistic chorus for greater self-sufficiency in food. Such an approach is superficially appealing in a British context. Globally, however, it would be a recipe for disaster.

The attractions of self-sufficiency are obvious. The idea has the ring of waste-not, want-not virtue about it. Farmers tend to like the concept. It bolsters the lifestyle and environmental case for consuming local and seasonal produce instead of imported food. It evokes images of Britons digging for victory in their own backyards.