From Prof Jeffrey D. Sachs.

Sir, Your article on the US's Trans-Sahara Counter-Terrorism Initiative ("Niger enrols in US global war on terror," October 1) sheds light on all that is wrong with the US approach to terrorism, Africa and foreign policy in general.

The United States' approach is almost exclusively militaristic. These days the military seems to be the US's first and last answer to any foreign problem. In the case of instability in four of the world's poorest countries -Chad, Mali, Mauritania and Niger - the US will train counter-insurgency forces, while utterly ignoring the underlying cause of instability in these countries: extreme poverty, hunger and disease which are among the most severe on the planet.

Niger's life expectancy is 46 years, more than 30 years less than the rich world's. Of every 1,000 children born in the country, 264 children die before their fifth birthday. The Sahel region has been experiencing a long-term decline in rainfall, which in turn is directly associated with increased outbreaks of civil unrest. Yet American official development assistance to Niger in 2002 (the most recent data) was Dollars 16m or Dollars 1.40 per recipient.

Aid to Chad, Mali and Mauritania totalled 84 cents, Dollars 4.32 and Dollars 1.96 per recipient, respectively. In societies too poor to even keep people alive, a military training programme will do nothing for stability in absence of an ambitious donor-financed effort to provide public services and move on to a path of economic development.

Overall, the US spends about Dollars 450bn on the military each year, compared with Dollars 15bn a year on official development assistance. The rest of the rich world is not speaking out forcefully enough in spite of the fact that the US and other rich countries promised in Monterrey, Mexico, to make concrete efforts towards contributing 0.7 per cent of gross national product in official development assistance.

The 0.7 per cent figure would amount to an additional Dollars 55bn or so per year. The acquiescence of the rich world in US neglect of its unfulfilled commitment on official development assistance is itself a danger to the world.

Jeffrey D. Sachs, Director of the Earth Institute Columbia University, New York, NY 10027, US