d U.S. intervention in the Russian Civil War (1918-1920) were still fresh in Stalin's memory when he took power. Furthermore, Stalin was bitter because he was not informed of U.S. nuclear capabilities until shortly before the atomic bomb was dropped on Hiroshima. Compounding tensions was the fact that Stalin's request that Russia be allowed to participate in the occupation of Japan was denied, even though Russia had declared war on Japan on 8th August (the bomb was dropped on Hiroshima on 10th August) and had been responsible for annexing south Sakhalin as agreed to at Yalta. This failure to be included in the Western world's politics created an even deeper rift between the two superpowers.
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