What Drove American Military Production in WWII?

What Drove American Military Production in WWII?: Historians have argued at length about how American industry converted from producing consumer to military goods during WWII. One group, represented by Paul Kennedy, essentially believes it was America's vast engineering force which refined mass production techniques to the point of mass efficiency. Another group, represented by Arthur Herman, emphasizes major American businessmen such as Henry Ford and Henry Kaiser. Either way, the federal government played a vital role in organizing the defense contracts that American companies desperately sought. For Kennedy's engineers, mass production of military goods had almost everything to do with feedback mechanisms. That is, engineers offered real-time responses to problems with military equipment that soldiers and sailors were having. And American engineers (people like Vannevar Bush and Crawford Greenewalt) were exceptional at developing feedback mechanisms, as soldiers/sailors were often able to fix their guns, tanks, airplanes, and ships on the front lines. Yet for Herman's businessmen, if there was one American industry which really adapted mass production techniques (assembly lines, interchangeable parts, etc.) for military purposes, it was automobiles, as Ford and GM each converted their plants to produce tanks, planes, half-tracks, etc.