Mikhail Gorbachev, who has died aged 91, was the most important world figure of the last quarter of the 20th century. Almost singlehandedly he brought an end to 40 years of east-west confrontation in Europe and liberated the world from the danger of nuclear conflagration. It was not the objective he set himself when he was elected general secretary of the Soviet Communist party in March 1985, nor did he predict or plan the way the cold war would end, the haemorrhaging of the Communist party, the withdrawal of Soviet troops from eastern Europe, the reunification of Germany or the break-up of the Soviet Union itself.
What distinguished Gorbachev from previous Soviet leaders was that he started a process of reform and did not try to reverse it once it threatened to spin out of control. The great facilitator, he carried on, even to the point of resigning with dignity as his power faded away.