By Paul Reynolds
World Affairs correspondent, BBC News website
At the Potsdam conference 60 years ago this week, Winston Churchill complained to Stalin that British diplomats in Romania were being penned in as if they were under arrest.
Wartime allies soon became rivals after the Potsdam meeting
"An iron fence has descended," he complained.
Churchill must have liked the sound of that phrase.
But perhaps it wasn't quite completely right. After all, fences do not descend.
So eight months later, on 5 March 1946, in Fulton, Missouri, he changed it slightly and managed at a stroke to sum up the division of Europe that rapidly followed the Potsdam meeting.
"From Stettin in the Baltic to Trieste in the Adriatic an iron curtain has descended across the Continent," he declared.
Potsdam marked the final end of the West's wartime alliance with the Soviet Union.
At Potsdam, the Cold War started.
It turned out to be a particularly pointless conference, though it was necessary in the circumstances - Germany had just been defeated, Japan was still fighting and Truman had taken over from Roosevelt.
During the meeting, as it turned out, Churchill was thrown out by British voters in favour of the reforming Labour Party under Clement Attlee.
President Harry Truman, ever the down-to-earth mid-westerner, never wanted to go to Potsdam anyway.
But he had to meet Churchill and Stalin. It was Stalin who insisted that the meeting be held in the Soviet-controlled sector near Berlin in an English Tudor-style country palace of the Prussian royal family.
"How I hate this trip," Truman wrote in his diary as the cruiser USS Augusta steamed towards Europe.
He initially trusted Stalin, as Roosevelt had done, though later to his credit he more than made up for it when that trust proved unfounded.
"I liked the little son-of-a-bitch," he wrote at the time.
He did not have much time to get used to Churchill as Attlee took over within days.
Churchill, Truman felt, talked too much and often talked a "lot of hooey."
A different world
Potsdam really only repeated the results of Yalta five months earlier - the division of Germany, the extension of Poland's western borders and the empty promises of free elections in Poland and other countries already in Stalin's sphere.
In his biography of Churchill, Roy Jenkins was dismissive: "By Potsdam there had set in a terrible sameness about the pattern of these summit meetings.
Winston Churchill lost power but remained an influential statesman
"It was like seeing the same not-very-good film several times round."
It took another 50 years or so for the results of Yalta and Potsdam to be undone.
And when it was, it was predicted that the end of communism would be the end of history. Not so.
We are now in the post-communist phase of world history. Conflict is still happening. History is therefore continuing, it appears.
There are new issues that would have seemed as far away from the discussions at Potsdam as those discussions are to us.
At the latest world summit, the G8 meeting of the world's leading industrial countries, aid to Africa and climate change topped the agenda..
During that summit, bombs went off in London. War continued in Iraq.
In 1945, Africa was a string of colonies, climate control did not exist (the Bankside coal power station, now London's Tate Modern gallery, was put up in just two years later) and Arab secular nationalism not Islamic radicalism was the growing philosophy across the Middle East, of which Iraq was a largely obscure part.
There is, however, one legacy from Potsdam with which we are still living.
While waiting in his lakeside guesthouse for the conference to start, Truman received word that the atom bomb had been successfully tested.
He felt compelled to tell Stalin that a new weapon "of unusual destructive force" had been developed.
The first atomic test was carried out as the leaders met at Potsdam
Stalin showed little interest. After all, he knew all about this from his own spies.
Japan was warned in the "Potsdam Declaration" that it could expect destruction if it did not surrender, but was not told of the bomb.
There was really no discussion about whether to use it. Everyone agreed that it should be, or Japan would have to be invaded.
On 24 July, Truman and Churchill met the American and British chiefs of staff and formally settled the matter.
On 5 August, while Truman was on the Augusta on his way home, the atomic bomb was dropped over Hiroshima.