Germany appears to have been caught up in a process of political momentum that propelled it into war before it was really ready, even according to its own strategic and economic projections. This momentum continued through the early part of the war, eventually producing the (as it turned out) disastrous invasion of the Soviet Union. By the time of that invasion, the momentum was such that those advising caution (whose ranks included no less than Hermann Georing) had little chance of prevailing; even speaking out for caution was, arguably, dangerous.
It is questionable whether Germany had the resources to take on the Soviet Union with confidence of victory at any point. One reason why the counsel of caution was ignored was a sort of complacency that seems to have pervaded much of Germany’s decision-making apparatus between 1938 and 1942. On the military and political side, the capacities of the Soviet Union to resist were unthinkingly underestimated. This is strange, as the Germans had had good opportunity to appraise the Soviet military during periods of positive co-operation between the two, notably in the period preceding Hitler’s assumption of power, and during the period of the Ribbentrop Pact. There were plenty of hints that the Soviet military, while in a shambles following the first officers’ purge, had the capacity to regenerate itself as a formidable fighting force. These seem largely to have been ignored. On the economic front, complacency may have been promoted by the Reichsbank’s brilliant performance in financing the government through the creation of “creative” financial instruments, and by the Nazi practice, even before 1939, of plundering the resources of their internal “enemies”, notably the Jews. The early victories (arguably lucky in many respects) greatly increased the opportunity for plunder which further masked the fundamental dearth of Germany’s resources for pursuing a major war in the East. The failure, or denial, of this fact resulted in policies that were inconsistent with the requirements of a major, possibly protracted war. Germany did not impose a “war economy” until the failure of the Caucasus-Stalingrad offensive, which finally destroyed the delusion that the essential plunder required of the Soviet Union (food, rare minerals and above all oil) would easily be secured. As much of the plunder secured in the West declined to a trickle, Germany’s fundamental resource deficit came to the fore - too late for the Germans to rectify the situation, however hard they tried. Complacency was replaced, increasingly, by desperation.
In this context, it is perhaps understandable that the new delusion of “wonder weapons” arose. Hitler himself promoted the development of what might be described as “political weapons”. Some of these reached operational capacity before the end of the war. Some had their impact but, given the great difficulty in securing the materiel and labour to produce them, few were produced in numbers sufficient to make much difference, and many were simply wrong-headed. Between 1943 and 1945, a great deal of labour, brainpower and materiel were diverted into developing “wonder weapons” of all sorts, for very little result. I have little doubt that these scarce resources would have been better employed in improving the practical weapons already available. But, in any event, after the Caucasus/Stalingrad debacle, the game was up for Germany in any event.
By the way - I am a bit puzzled by the suggestion coming through in some of these posts that the “early French surrender” was something like a strategy for the French. This certainly does not chime with the activities of the French government as the German invasion proceeded. But then, the real problem was the “French government”. Petain’s assumption of power was the culmination of the unhappy history of the French Third Republic. At the outset of the invasion, the French government was divided between those determined to resist, and right-wing elements less inclined to do so. The latter had an ulterior motive - the destruction of the Republic, and its replacement by some ill-defined reactionary regime. For this, they appear to have been willing to tolerate a defeat at the hands of the generally-unpopular (even among French Right-wingers) Germans. In the event, the reactionary Right were successful in this, manipulating the government and parliamentary apparatus to produce the Pétain coup. The result was the institution of the "État Francais, a sort of monarchy without a king, but with a “Head of State”. This was the real objective of the reactionaries - the destruction of the Third Republic, whatever the cost. France (even the “Occupied Zone”) continued under this odd régime until the Liberation. For the people of France, oppressed and plundered, this was hardly a good outcome. Best regards, JR.