The popular conception of World War I centers on hellish trench warfare and all its horrors. While it is undeniable that the war was won and lost on the Western Front, the lines stretching back across the Atlantic that brought men and desperately needed supplies into the theater of operations played an essential part in Allied victory.
Death from Below, Salvation from Above: The Effect of Civil-Military Relations on British and Japanese Anti-Submarine Warfare Strategies in the World Wars
In the two largest wars this planet has ever experienced, the authority and influence of civilians over military affairs assured victory in one and the lack of such brought total and utter defeat in another. Therefore, in the grand scheme of things, civil control of the military has proven its value not only as an avenue for better governance, but as a strategic asset capable of providing the necessary leverage to achieve victory in wartime.