The past week has marked the 70th anniversary of Yalta, one of the most controversial diplomatic conferences in modern history.

On 4-11 February 1945, the 'Big Three' political giants of the Allied cause – US president Franklin D Roosevelt, British Prime Minister Winston Churchill and Soviet dictator Josef Stalin – gathered in Yalta, a small town in the Soviet Crimea.

The goal of the conference was to shape a post-war peace that represented not just a collective security order but a plan to give self-determination to the liberated peoples of post-Nazi Europe. In short, it reflected Woodrow Wilson's vision at Versailles nearly a quarter century earlier.

But Yalta, as most diplomatic historians recognise, failed. It set the scene for the Cold War. We now know that a naive FDR and war weary Churchill caved in to the manipulative Stalin's demands. They accepted what proved to be false assurances that free elections would be held in eastern Europe. Such elections were never held during the next 40-odd years of the Cold War.

FDR died in April 1945 and Churchill lost a landslide election in July that year. But within months of Yalta, Stalin had imposed communist dictatorships under Soviet control; he remained in power until 1953.

As Churchill warned at Fulton, Missouri 13 months later, 'an Iron Curtain' was descending across the continent. It led to the brutal crushing of the Hungarian Revolution of 1956, the suppression of the Prague Spring in 1968, and the imposition of martial law in Poland in 1981.

Churchill's 'Iron Curtain' speech did not just shape the thinking of generations of Cold Warriors in the West – from Konrad Adenauer and Robert Menzies to Margaret Thatcher and Ronald Reagan. It also inadvertently recognised that Yalta was a failure. Ever since, Yalta has become a symbol of betrayal; a dirty word in diplomacy. 'No more Yaltas' became the new diplomatic orthodoxy. A costly lesson in Western gullibility, Russian duplicity, and great power deals at the expense of the weak, it was said. If only Washington and London had been tougher on the Soviets. If only FDR and Churchill had been more suspicious of Stalin.

George W Bush reflected the accepted wisdom in 2005 when he declared Yalta as 'one of the greatest wrongs of history.' At Riga in May 2005, the US President insisted: 'We will not repeat the mistakes of other generations – appeasing or excusing tyranny, and sacrificing freedom in the vain pursuit of stability.'

The issues that have made Yalta so controversial are as relevant today. They confront Barack Obama, David Cameron, Angela Merkel and other Western leaders in their standoff with Russia. What should have been asked about Stalin 70 years ago this week has been asked about Putin today: can Moscow be trusted? Can Russian ambitions be limited by diplomacy? Will the Kremlin honour agreements?

But there is a difference between the Soviet Union and post-Cold War Russia. Stalin's intervention in Eastern Europe was designed to transform the international state system in his communist image; Putin's incursion into Ukraine is a way to protect a buffer zone. Stalin was not responding to any Western encroachment upon Russia's near abroad; Putin is responding to years of NATO and EU expansion that culminated in the Western-backed coup to topple a democratically elected pro-Russian government in Kiev a year ago.

The West's containment of the USSR was a great ideological and geopolitical cause; pushing Russia into a corner is pointless and playing with fire. In dealing with the Soviet Union, a genuinely imperialistic power, compromise and accommodation represented weakness. But in dealing with Putin's Russia, a traditional great power with modest regional ambitions and legitimate security interests, compromise and accommodation make sense.

At Yalta 70 years ago, FDR and Churchill were driven to a fallacious deal by recognition of what they perceived to be common interests. Just because that plan failed does not mean the need for a similar US-Russian compromise over Ukraine is any less urgent today.

Photo courtesy of Wikipedia.