To make a long story short, Stalin supported and strengthened Hitler, baiting him to start World War II against Britain and France with the anticipation that the western capitalist countries would so weaken themselves that the expansion of Soviet communism would be free to clean up and take over the remains.  Just before Stalin was to invade Germany, Hitler struck first.  The rest is the history with which we are familiar.

Through either an email or comment (I don't recall which) I was introduced to the work of Mark Solonin.  With his permission, I offer a brief review of one of his posts, entitled Comrade Stalin's Three Plans.

He begins with a statement that is agreeable to all – whether one believes Suvorov's account or the more traditional version:

The fact is that Hitler's attack on the Soviet Union at dawn on June 22, 1941 became a horrible surprise for Comrade Stalin.

Germany's attack astonished the inhabitants of the Kremlin's offices, stunning them and putting them into a state of shock. That is the fact.