then he overreached
[Map found on “unsplash;” red dots are irrelevant.]
Back when war was thought to be a glorious undertaking, nations would actually publish their “war aims” upon getting involved in one. Germany’s aims for itself regarding the conflagration that would become known as World War I were actually rather modest: primarily, force limited territorial concessions in northwestern Europe to provide Germany more “ore” and a direct outlet on the Atlantic Ocean, and a formal acceptance of Germany’s recognized, if not formally institutionalized “economic dominance over “Mitteleuropa,” to include France. Tellingly, it explicitly left the “question of Russia” for later — and made no mention of England (other than noting in passing how accomplishing its aims would affect its relations with that nation).
When France surrendered on June 25, 1940 following Germany’s onslaught to the west in World War II, Hitler’s Germany had accomplished all that and more. Germany had taken all of mainland Europe (except neutral Switzerland) between the Alps and the Pyrenes Mountains, east to west, and the Baltic and Mediterranean Seas, north to south — plus Norway to the north as well as half of Poland and all of Austria and Czechoslovakia to the East of Germany.
So in the early Summer of 1940 Hitler had achieved everything Germany had hoped to achieve militarily in WWI and much more. Had he opted to stop there, who knows how history would have evolved? Instead, he overreached.
Germany’s goals for WWI did explicitly include a “continuous colonial empire in Central Africa.” In WWII that was not a goal, but in June of 1940 Hitler made the fateful decision to move militarily into North Africa to take the Suez Canal from Britain and to gain access to oil (the importance of which was just becoming a part of nations’ calculations). That was his first mistake.
Next, he took on England directly. Rather than invade, he sought to ‘bring her to her knees’ through a campaign of aerial bombardment.
Finally, Hitler made his fatal mistake: (too) late in the Summer of 1941, Germany invaded the U.S.S.R. Failing in North Africa and failing to defeat England would be setbacks, but even both together would not of themselves have threatened the existence of Hitler’s Reich. Attacking the Soviet Union and failing to defeat it—especially given that England was still unconquered — doomed Germany to inevitable defeat. Declaring war on the U.S. in December of 1941, following its declaration of war on Germany’s ally Japan, sealed the deal.