LAURENCE REES: And then they meet together for the first time at Tehran in November 1943. How important was the Tehran meeting?

ROBERT SERVICE: I think it was extraordinarily important that the three leaders eventually got together. At that time at Tehran it was still the case that both the British and the Americans needed the Soviet war effort and actually, of course, for the next year or so they fully expected to need them, not just on the Eastern Front in Europe but eventually against the Japanese. The need for the Soviet Union conditioned the bargaining that went on among the big three. It was only right at the end of the war when the Americans found that they could finish off the Japanese by unleashing the atom bomb that the British and the Americans decided that they didn’t want the Russians in Japan at all, but by then the agreements had been gone into and it was too late to stop the Red Army from moving eastward into Manchuria.

LAURENCE REES: And of course at Tehran what they Western Allies essentially do is to agree that Stalin can keep the territory in Eastern Poland he wanted, something that less than two years before in January ’42 Churchill had said was an impossibility, so why this shift?

ROBERT SERVICE: It’s certainly true that Churchill and Roosevelt turned their backs on Polish national interests and they did so because they needed the Soviet Union involved in the war effort, and they quietly and confidentially decided that leaving Stalin with the lands that he’d taken from the pre-war Polish state was the price that had to be paid. And one can see why Poles today continue to look on this as a betrayal, when you consider the number of Polish airmen who fought in the Battle of Britain, crucial elements in Britain’s self defence.

LAURENCE REES: Did Rooesvelt and Churchill really have to cut this deal?

ROBERT SERVICE: I think that what Roosevelt and Churchill did was too hasty and too clear-cut, and I think they stuck far too fixedly to the deals that they’d done with Stalin at Tehran and then at Yalta. If we look at it from the Soviet side, Stalin had a greater capacity for reneging on deals than the other two of the big three had, and, yes, I think that chances were missed in 1944 and 1945 when more demands could have been made on Stalin than actually were made.

LAURENCE REES: What could they have done differently?

ROBERT SERVICE: They could have insisted that democratic elections, patrolled by all of the Allies, took place in all of the countries freed from the Third Reich.

LAURENCE REES: But how? These countries are occupied by Stalin. We’re not going to send in troops if he doesn’t agree or drags his feet or puts obstacles in the way of any people who are there. There’s almost nothing that can be done to make it happen.

ROBERT SERVICE: It would have been very, very difficult, but in 1945 Stalin was looking for a big financial loan from America, and it’s only in 1947 that that becomes obviously impossible. The Americans weren’t going to give that money. In 1945 the Americans had a much stronger ability to stand up to Stalin in Eastern Europe and East Central Europe than they had in 1947 when half communisation had already taken place in all of those countries. So it would have been asking a lot of the Americans and the British to do this. But they didn’t do it at all robustly in 1945 and 1946 and that, I think, is a tragedy, because by 1947 the instruments of full communisation were already in Stalin’s hands in Eastern Europe.

LAURENCE REES: And going back to the Warsaw uprising you mentioned. Why did Stalin refuse to help the Poles in Warsaw in 1944?

ROBERT SERVICE: Stalin took the view on the Warsaw uprising that it was being conducted by the worst sort of Poles. They were patriots, they didn’t like the Russians, they didn’t want communism, so if he rushed the Red Army, which was exhausted, battered and needed a rest, across the River Vistula to Warsaw what would he be doing? He would be liberating Poles who were going to give him trouble. So he cynically took the view that it would be very useful for him to enable the Germans to exterminate what Stalin thought was the worst sort of Polish people.

LAURENCE REES: And, of course, even without ordering the whole of the Red Army forward, Stalin could have offered air bases to the Western Allies and other aid.

ROBERT SERVICE: He behaved with supreme cynicism. He took a narrow view of the Soviet national interest and of the interest of the spread of communism, and he let the Polish uprising be exterminated brutally by the Germans. He knew what he was doing. Ironically, this was the same man who said, why on earth can’t you send the American and British fleets over the English Channel and invade France? The much smaller division which was the River Vistula was too much, apparently, for the Red Army. So he was a brute. When all is said and done he was a brute.

LAURENCE REES: So let's think about the Yalta conference in February 1945. To what extent can we say that Yalta was a betrayal of the ideals the West said they were fighting a war for?

ROBERT SERVICE: Geopolitics took over from idealism; the Allies did geopolitical deals that were softer than the ones that everyone thought they were fighting the war for. So Yalta involved concessions to the Soviet Union that were definitely going to give the Kremlin influence over Eastern Europe and East Central Europe that at the start of the war no one had thought conceivable. And the Soviet Union is treated as one of the big three powers in the world. It’s in this period, 1944 and 1945, that the Soviet Union emerges as one of the superpowers, a superpower on the way up, whereas the British superpower is already in decline. So deals are done. It’s understandable that both the British and the Americans sought to find ways of ending the war that would limit the number of soldiers and civilians that they lost, and would ease the way towards peace, but in the process nations were liberated from the Third Reich only to find that they were subjected to the iron heel of the Soviet regime.

LAURENCE REES: So would you agree with the statement that Yalta was a betrayal of the ideals the West said they were fighting a war for?

ROBERT SERVICE: I think that Yalta involved a betrayal of some of the ideals of the three Allies, as explained at the beginning of the alliance. Obviously so many of the effects of the victory were of a positive nature. I mean, the Third Reich was eliminated, the German Empire had ceased to exist in Europe, but there were national casualties, and those national casualties were all of the countries to the East of the iron curtain. Half of Europe.