I was thinking about a timeline where Adolf Hitler dies in late 1938 and Hermann Goering takes over as the Fuhrer of Nazi Germany. Then, I have Stalin grow even more paranoid that he takes a risky gamble: invasion of Poland in the '40s (probably ASB). The UK, France, Italy and Nazi Germany declare war and defeat the USSR.
So, what would Japan do? The US? What kind of Fuhrer would Goering be?