Why did Hitler believe Japan would invade Russia after Germany did?

Answer 1

Hitler believed this because Japan and the Soviet Union experienced tensions with each other among the Manchukuo border. Japan also wanted the Soviet Union completely out of Asia, so Hitler had hoped that Japan would assist Germany in the destruction of the Soviet Union. However, Japan had instead opted to move into Southeast Asia and to engage the United States and Great Britain in naval warfare instead. But in 1939 Germany signed the "Pact of Steel" agreement with the USSR. Japan felt betrayed by this pact and would view Germany with suspicion. Japan has always viewed the West with suspicion since they were betrayed at the end of World War I. Hitler declared war on the US after Pearl Harbor, in hopes to regain confidence from Japan, hoping they would return the favor and declare war on USSR. But this would never happen.

In March 1941 the Japanese informed Hitler that they were going straight for the jackpot, the U.S. So when Operation Barbarossa started he knew that he wouldn't be getting any help from Japan. The primary reason is that Russian and Japan still did not trust each other after the Russo-Japanese War that was a border clash fought between 1904-1905.