Since food is the most basic of human needs, it is not surprising that food security is a sensitive policy concern, particularly in countries that are somewhat dependent on food imports and that have experienced interruptions to import supplies. European countries felt that acutely during and following World War II, which led them to develop a Common Agricultural Policy (CAP) soon after the formation of the predecessor to the European Union, the European Economic Community (EEC). A key objective of the CAP was self-sufficiency in basic foods. Likewise, Japan sought imperial rice self-sufficiency in the first half of the 20th century (Anderson and Tyers 1992). After it lost its colonies of Korea and Taiwan in 1945, Japan then sought national self-sufficiency for rice and a range of other farm products. More recently, numerous developing countries have placed long-run food self-sufficiency high on the list of their policy priorities.

The first section of this chapter explains why attempts to reach long-term food self-sufficiency using farm trade barriers are more likely to undermine than to boost national food security – and at the same time reduce prospects for export growth by competitive farmers in more-open developing countries.

Trade measures are also brought into play to deal with short-term food security concerns, such as at times of international price spikes. By altering food trade restrictions at a country's border, governments hope to insulate their domestic food markets from international price volatility. This chapter's second section explains why such actions by a combination of food exporter and importer countries will offset each other and, at the same time, exacerbate those fluctuations in the international marketplace for other countries.

Trade policies and long-run food security

Achieving long-term food self-sufficiency is possible for all but the most densely populated countries simply by banning imports of food. That raises domestic food prices, which encourages local farmers to increase their production. The domestic price rise also discourages food consumption, however. That trade policy therefore undermines food security, which refers to the condition in which all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life (FAO 2015).