LAURENCE REES: Why do you think it made sense to Stalin to make a pact with the Nazis in the summer of 1939?

SIMON SEBAG-MONTEFIORE: Well, I think genuinely that they did look at the other options, they did look at France and England, which Stalin naturally regarded as real enemies back from the Russian Civil War days. There had to be an extra burden of serious intention and the British and the French really didn’t show any gravity or serious commitment to protecting the Soviet Union. When they sent their delegations they sent them by ship and they didn’t give them proper powers of attorney or even a proper agenda or programme. So while Stalin, under great pressure, is looking at these different alternatives, the British and the French were never offering anything that Stalin really needed, while the Nazis were offering exactly what he needed. Stalin was always aware that he had to choose between one of these two options and I think that of course he found democracies contemptible and their decision making processes absurd, and their slowness and their cumbersomeness - these were all things that he just didn’t understand.

He also regarded them as capitalist countries and as due for the chop at some point. He had a hugely exaggerated view of the power of the British Empire, but also of its sort of sinister intentions towards the Soviet Union. But I think when he realised that they weren’t serious, that there was going to be a war and that they seemed weak and listless, the Nazis seemed a much better bet, and I think he was always aware that there was going to be a war with Hitler so he wasn’t tricked by Hitler in that sense, but I think that he thought he could win many more years out of Hitler and also a much better deal than he would ever have got from the British or the French. So in all these ways he really had no choice but to go to the Nazi pact. There wasn’t another offer on the table that meant anything.

LAURENCE REES: And do you think that he always believed - even at that stage - that it would come to war eventually between the Soviet Union and the Nazis?

SIMON SEBAG-MONTEFIORE: I think he did. He talked about that all the time within his inner circle, that the Nazis were the first enemy and when he got to the pact he talked quite openly with his inner circle about the fact that it was necessary to buy some years. His actual dream scenario was that the Nazis would never get round to attacking him because they’d be so busy fighting the British Empire and France on the Western Front, and that he’d just wait and would be able to pick chestnuts out of the fire, as he put it, and that therefore Russia would never be attacked by the Nazis after all.

The nightmare scenario was exactly what happened, that France would be totally defeated - that was unthinkable to Stalin. He seriously thought that the war would come and he was never in any doubt that there would be a war and that Hitler had ultimately hostile intentions towards him, and he constantly said when he was talking to Molotov and Kaganovich and all these top people that the Nazi attack would come but he thought they’d put it off till 1942, ’43, ’44. He knew that they [ie the Soviets] had to recover. And the key thing was after the purges he knew that he’d absolutely wiped out the officer corps and that the army was ill trained and that its whole strategic philosophy was in a total mess, and so he knew that he had no choice but to wait. He knew it would be a disaster otherwise.

LAURENCE REES: And did Stalin ever have any intention of attacking the Nazis himself?  There was that minority view at one time that the Soviets might have been planning a pre-emptive attack in 1941.

SIMON SEBAG-MONTEFIORE: I don’t believe that sort of line of approach. If you look at the plans of any general staff or any state in existence they always have both defensive and offensive plans. The fact that they exist means nothing. I mean he certainly prided himself and the Red Army prided itself on its total offensive ability and the fact that its philosophy was always aggressive, that was its style. He always talked about how they would immediately go on the offensive and all this kind of thing, but actually the plans that were there were never really signed off by Stalin, and he was extremely cautious in all matters of foreign policy. He took a very old-fashioned Bismarckian sort of 19th Century view. And one forgets that these people were all children of the 19th Century. Hitler was the maverick in this. Hitler was the exceptional one and one should see Stalin, though not in the context of revolutionary radical foreign policy, in terms of a 19th Century real politique. And that’s what he was, that’s where he was at home, that’s how he thought.