lagopus
Few in the US know that Neville Chamberlain was a member of Churchills war cabinet after he was replaced by Winston. He was till a respected member of the government with a strong following. His dithering did in fact by time for his country but if he had been able and willing to make Hitler back down Hitler may have been replaced before the war even started. History is full of these what if type questions. If Custer had taken the Gattlening guns with him, as he was supposed to, it may have been Sitting Bulls Last Stand not his, that day many years ago.
Now in the end the WWII may still have happened. And if the start had been delayed by five years or more, as the German original time table was based on war in 1944 or 1945, two major weapons Germans were working on would have been operational. Just think of 2000-3000 jet fighters and the A-bomb in the hands of the leader who had forced out Hitler. First A bomb a air burst over Paris, France surrenders. Second one over England and they would be forced to follow. German victory in a short few months of war. How long would Russia last then? Months. Maybe the achievement of Neville Chamberlain was his appeasement bought enough time for England but not enough time for Germany.