Letters: How to save red squirrels

Fire-fighting

Sir: Your editorial raised the persistent problem of predicting major international disasters in a timely enough way to prepare (‘Eclipses and revolutions’, 29 April). The US academic Joseph Nye said that a good model for wars is to identify three types of cause: deep (the logs for a fire), intermediate (the kindling) and immediate (the sparks). The dilemma is that there are often so many crises on the brink of igniting that preparing early for dozens stretches many governments.

Struan Macdonald

Hayes, Kent

Brain drain from Africa

Sir: The majority of Sudanese doctors working in Britain will have been trained in Sudan at local government expense (Eclipses and revolutions’, 29 April). But pay and conditions being what they are in most of Africa, over the years these doctors have successfully negotiated their way to greener pastures in the West, and the NHS was quite happy to poach them. The medical brain-drain system is widespread across Africa and continues to contribute to the poor health of its people.