U.S. ARMY AND IMPERIAL JAPANESE ARMY DOCTRINE DURING WORLD WAR II
Doctrine provides an insight into an army's concept of warfare, how an army thinks about itself. Links between doctrine and an army's force structure offer an appreciation of the army's tactical and operational methods of executing that doctrine. For instance, if an army understands warfare as primarily an affair decided by the infantry, a doctrine emphasizing infantry tactics, morale, and leadership qualities might emerge. Another army that understands warfare as a matter of combined arms may highlight weapons technology and machinery. No such clear-cut dichotomy exists in real armies, as the differences of emphasis are mainly those of degree, not exclusion. Nevertheless, armies do disregard unfeasible means of warfare, because they cannot afford to consider or invest seriously in doctrines and force structures that they lack the potential resources to implement.
It made no sense, for example, for the IJA of the 1920s and 1930s to ponder heavy divisions and armor units, because they lacked the industrial capacity and natural resources to augment such a force structure. It did, however, make sense for them to concentrate on infantry tactics and design a doctrine based on infantry spirit overcoming technological deficiencies. Similarly, for the Americans it made no sense to build 175 infantry divisions when a strategic air force, armored divisions, or Lieutenant General Lesley McNair's pooled artillery and tank concepts could be realized. In short the basic American strategic decision to out-