>>Actually it was a lot more complicated than that. Japan, China, Russia, Italy, Austria and North Africa were all strategic and commercial factors and Hitler put them all into play early in the game.
>>At the rate he was building his armaments and Navy, if unchecked, he could have made the game unwinnable for Britain.

He didn't have a problem with Britain and didn't declare war on it. The stated goal of the Czech and Polish invasions was for lebensraum, more room for Aryans to live and farm. Had the Brits and French not declared war and assuming invasions were to continue: Russia would have been next. FWIW, Russia also invaded Poland in 1939 and collected its share, but nobody declared war on it. Nor was there post-war recrimination for the shocking Russian persecution of the Poles. Ethnic cleansing, deportations, mass murders... it was all there. Two wrongs don't make a right, but you can't ignore Britain and France's declaration of war on Germany but not Russia.

>>In Mein Kampf Hitler referred to Britain as a valued ally and spoke admiringly about the US, but he made no bones about his intention to invade Russia and hinted about France.

Agreed re Britain and the US but depending what you read, Hitler may have believed very early on that a clash with the US is inevitable one day. Meanwhile of course he did invade France- but only after France declared war.

Probably we'll never know for sure and the lesson that ought to resound through the ages is that war is crazy and the winners are those who are best at confining the mayhem to foreign fields. Which was the US in WWII, FWIW. The problem in 2015 is that the enemy brings the fight into our towns and cities and has nothing to lose if their own towns already are bombed out or decimated by sanctions or swarming with radicals.