One (significant) historical point--conservatives didn't support Stalin.  They were terrified of him.  That's why Henry Ford, the Duponts, Lindbergh, W. R. Hearst, Joseph Kennedy, Prescott Bush, Rockefeller, Dulles and many more of America's "upper-crust" sympathized and/or collaborated with the Nazis prior to the outbreak of WWII (and some after).  Not because of Stalin's atrocities, but because of his ideological threat to their properties and privileges.

Ten times during the run-up to the war Stalin appealed to the "allies" to sign a non-aggression pact with the Soviet Union, and was rebuffed.  They were counting on their boy Hitler to eliminate him.  So Stalin accomplished a tactical stroke of genius--he made the same offer to Hitler.  This practically GUARANTEED that Hitler, whose entire economic recovery was founded on the buildup for war, would be forced to first attack his western European benefactors before turning on Russia.

Dance with the devil, the devil don't change...