While it would be quite wrong, then, to claim that the outcome of the First World War was predetermined, the evidence presented here suggests that the overall course of that conflict—the early stalemate between the two sides, the ineffectiveness of the Italian entry, the slow exhaustion of Russia, the decisiveness of the American intervention in keeping up the Allied pressures, and the eventual collapse of the Central Powers—correlates closely with the economic and industrial production and effectively mobilized forces available to each alliance during the different phases of the struggle