@CWO-Marc
Yes, this topic is fascinating.
The long analysis would appear to be that Hitler took full advantage of the weakness of the political resolve of his rivals and adversaries in the period 1936-1940 when Germany was still quite weak. This incorporated a complex series of threats, posturing, “divide and conquer” and limited military action (after demonstrating some of Germany’s effective and innovative, though limited, technology and doctrine to great effect in the Spanish CW).
However, after series of stunning successes leading up to Poland and France, and peaking with stunning defeats of those two powers (using the new tactics and technology) Hitler essentially ran out of low hanging fruit. The experiences of Napoleon, Tsarist Russia and Prussia amply demonstrate that there is nothing like a meteoric rise to power to turn all your former enemies into mutual allies.
Hitler did not excel as a traditional diplomat or strategist–he played a series of gambits that suceeded by momentum and the confusion and disunity of his enemies. But that very process reversed itself quite dramatically into the concept we today call the Allies–a unified group of powerful and imperial nations with access outside the world island (eurasia) to resources and manpower Germany could not hope to match. Napoleon and Hitler were greatly stymied by the “contiental system”–they did not control access to the sea (and not even a real navy as in WW1), resources or the wider world and therefore had to either win that access quickly or be surrounded and besieged from every side.
This, and the myths that existed within the German zeitgeist of US social disunity, UK broken resolve, and USSR incompetence and barbarity were crucial underestimations of their foes. H’s ideas about the deeper weaknesses of his enemies were based on tremendous misconceptions about history and contemporaneous events that can only be understood by a closer examination of H’s personal mindset and the NSDAP’s rise to power.