Critics of the bomber offensive frequently argue that the material and human cost of the campaign far overshadowed the gains, and that the resources dedicated to it could have been more effectively utilized elsewhere. They have argued that the combat manpower could have been better used in the other fighting services, especially the army, and industry could have been used to produce more weapons for these fighting services. However, proponents of this line of thought assume that the weight of effort expended on the bombing campaign was inordinately high. Richard Overy maintains that it was actually rather modest. “Measured against the totals for the entire war effort (production and fighting), bombing absorbed 7 percent, rising to 12 percent in 1944–45. Since at least a proportion of bomber production went to other theatres of war, the aggregate figures for the direct bombing of Germany were certainly smaller than this. Seven percent of Britain’s war effort can hardly be regarded as an unreasonable allocation of resources.” Further, although some significant infantry shortages were experienced in 1944, they never reached an extremely critical overall level and were eventually rectified. With respect to materiel, none of the services was conspicuously wanting for anything by 1943, and the British effort was thereafter bolstered by substantial North American war production.
Bashow, David L. "The Balance Sheet: The Costs and the Gains of the Bombing Campaign." Canadian Military History 15, 3 (2006)