On Christmas day 1979, 30 years ago, Soviet forces poured into Afghanistan. Two days later Soviet special forces killed Hafizullah Amin, president, in his Kabul palace. The Russians imposed their puppet, Babrak Karmal, in his place. Led by Jimmy Carter, the US president, and Margaret Thatcher, the UK prime minister, the world united against this latest example of cynical and ruthless Soviet imperial aggression against a small neighbour. Financial, economic and military assistance to the growing insurgency flooded in from Pakistan, China, Saudi Arabia, Iran, the US and Britain. Nine years later, on February 15 1989, the Soviets withdrew, a superpower humiliated by a rag-tag army of pious peasant fighters armed by Charlie Wilson, US congressman, with the Stinger missiles that drove the Soviet battle helicopters out of the sky.

