Monitoring nuclear weapons1

Abstract

America’s first space program was to develop surveillance satellites to monitor the nuclear arsenals of the Soviet Union and its allies. Although the Cold War has ended, nuclear weapons remain a threat to world peace and surveillance satellites are still an important tool in monitoring them. A recent US policy statement on the subject stated that “The threat of nuclear war has become remote but the risk of nuclear attack has increased”.2 An all-out nuclear exchange between the USA and Russia looks very unlikely, but nuclear weapons are now held by nine countries, some in areas of the world where the threat of war is high. 3 Recent calculations suggest that a nuclear war between regional powers could cause a decade-long global winter, with a death toll of about a billion (mostly among those who live on marginal food supplies).4