The alliance between the Western democracies and the Soviet Union during World War II has long been obscured by decades of Cold War rhetoric. The recent commemoration of the D-day landing in Normandy has again highlighted the fact that brotherhood in arms with one's ideological foe was a major embarrassment for political leaders both in the West and in the East.Each side dealt with this embarrassment with different propaganda tactics. In the West, the Soviet war effort was obscured as much as possible. As a result, D-day was heralded as the turning point of the war although, from a purely military point of view, this was not true.Soviet propaganda, on the other hand, focused on Western treachery, claiming that we fought and won the war against Germany and then the West just came in at the end to gather the spoils.On both sides, this propaganda was effective, especially in Russia. Whereas in the West -- particularly in the United States -- the general public is simply ignorant, in Russia it is openly hostile.From 1941 to 1943, the Russian army waged a battle that often seemed hopeless. With their backs to the wall, the Soviet army was desperately looking for help. But the second front in France did not materialize, neither in 1942 nor 1943 as our Western allies had promised.In reality, the West did not have the military capability for a full-scale invasion of France earlier than the summer of 1944. Their promises to move earlier were just an attempt to boost Russian moral. But the effort backfired, and the Russians felt betrayed, vulnerable and isolated.The situation is similar now. Many Russians -- including the Russian military -- feel weak, vulnerable and isolated. The D-day celebration was just one more lost opportunity to prove the contrary. Air Marshal Yevgeny Shaposhnikov told me last week: "It's a shame they didn't invite us. And, at the same time, NATO is planning to expand to the east."Of course, Russian troops did not actually take part in the D-day landing. They were fighting the Germans on another front. For that matter, in no major battle of the war did Russian and Western troops fight side by side. As a result, it will be hard to find a place and time to stress the wartime partnership. Last week authorities in Berlin formally barred Russian troops from taking part in a joint military parade with Western allies in West Berlin this July.There has been too much talk of "winning the Cold War" in the West, with Russia the loser by implication. The Russian army has not been defeated in battle. Creating the impression that a nuclear superpower has its back to the wall again cannot be the best possible policy.Pavel Felgenhauer is the defense and national security editor for Segodnya.