If one strand in the heritage of the Sixties was high-cultural pretension, the other, its intimate inversion, was a hardening crust of knowing cynici… - Tony Judt

Gorbachev did more than just let the colonies go. By indicating that he would not intervene he decisively undermined the only real source of political legitimacy available to the rulers of the satellite states: the promise (or threat) of military intervention from Moscow. Without that threat the local regimes were politically naked. Economically they might have struggled for a few more years, but there, too, the logic of Soviet retreat was implacable: once Moscow started charging world market prices for its exports to Comecon countries (as it did in 1990) the latter, heavily dependent on imperial subsidies, would have collapsed in any event.
As this last example suggests, Gorbachev was letting Communism fall in eastern Europe in order to save it in Russia itself—just as Stalin had built the satellite regimes not for their own sake but as a security for his western frontier. Tactically Gorbachev miscalculated badly—within two years the lessons of Eastern Europe would be used against the region’s liberator on his home territory. But strategically his achievement was immense and unprecedented. No other territorial empire in recorded history ever abandoned its dominions so rapidly, with such good grace and so little bloodshed. Gorbachev cannot take direct credit for what happened in 1989—he did not plan it and only hazily grasped its long-term import. But he was the permissive and precipitating cause. It was Mr Gorbachev’s revolution.

This distrust of short-term memory, the search for serviceable myths of anti-Fascism—for a Germany of anti-Nazis, a France of Resisters or a Poland of victims—was the most important invisible legacy of World War Two in Europe. In its positive form it facilitated national recovery by allowing men like Marshall Tito, Charles De Gaulle or Konrad Adenauer to offer their fellow countrymen a plausible and even prideful account of themselves. Even East Germany claimed a noble point of origin, an invented tradition: the fabled and largely fabricated Communist 'uprising' in Buchenwald in April 1945. Such accounts allowed countries that had suffered war passively, like the Netherlands, to set aside the record of their compromises, and those whose activism had proven misguided, like Croatia, to bury it in a blurred story of competing heroisms.
Without such collective amnesia, Europe's astonishing post-war recovery would not have been possible. To be sure, much was put out of mind that would subsequently return in discomforting ways. But only much later would it become clear just how much post-war Europe rested on foundation myths that would fracture and shift with the passage of years. In the circumstances of 1945, in a continent covered with rubble, there was much to be gained by behaving as though the past was indeed dead and buried and a new age about to begin. The price paid was a certain amount of selective, collective forgetting, notably in Germany. But then, in Germany above all, there was much to forget.

The outcome of the Berlin crisis showed that the two Great Powers had more in common than they sometimes appreciated. If Moscow undertook not to raise again the question of Allied status in Berlin, Washington would accept the reality of East German government there and would resist West German pressure for nuclear weapons. Both sides had an interest in stability in central Europe; but more to the point, the US and the USSR were both tired of responding to the demands and complaints of their respective German clients.