How did Hitler help the Allies win World War 2?
Well, he didn't 'actively' help the Allies win, but when people
say that Hitler was his own worst enemy, they have a point. You
have to remember that people like Hitler have instaiable appetites
for power, there simply is no limit to their desire to conquer.
Hitler's decisions after Germany's triumph in the Battle of France
are questionable, ie. invading the Soviet Union before concluding a
peace with Greeat Britain. Strategically this led to a two front
war which Germany always sought to avoid. Furthermore, Hitler's
meddling often proved disatrous, his 'no retreat' policy deprived
the German Army of what was ostensibly its greatest asset (mobile
warfare and tactical flexibility).