Why a long war favoured Allied industrial depth

Quick operational victories differed from the demands of a long industrial war. Denmark was overwhelmed rapidly, and Norway's delayed mobilisation helped Germany, but neither case proved that the Axis could sustain years of global fighting. Once maintenance, replacement, and continuous construction became decisive, Germany faced the resources and strategic depth of the British Empire. The Axis then widened the conflict to include the Soviet Union and the United States, adding another vast industrial state and a dictatorship willing to absorb extreme losses to Germany's opponents. On this argument, the Axis lacked viable industrial odds once the war reached that scale, a judgment that does not diminish the cost of resisting it.