AFRICA'S importance for global security has risen dramatically in recent years. Africa has served as a staging-post for terrorist attacks both within the continent and in the Middle East. West Africa's development prospects have brightened with the discoveries of offshore oil and gas reserves that could supply perhaps 25% of America's hydrocarbon imports within a decade, yet the orderly and transparent development of these reserves is threatened by violence and instability. Al-Qaeda has reportedly tapped into the illicit diamond trade in west Africa and has promoted insurgencies across the Sahel (the border region between desert and savannah). Governments in countries such as Ethiopia, Kenya, Tanzania and Uganda are co-operating closely with America to fight these threats. But poverty, hunger and disease leave the region vulnerable to security and humanitarian disasters.

In every aspect of Africa's complex plight an ounce of prevention will be worth a ton of treatment. In recent years America gave a negligible $4m a year to Ethiopia to boost agricultural productivity, but then responded with around $500m in emergency food aid in 2003 when the crops failed. In the 1990s America gave less than $50m a year for Africa to prevent AIDS, so now will spend $3 billion per year to treat the disease after it has spread to more than 50m Africans—20m dead and 30m currently infected (see article).