This monograph examined the newly announced Associated Units Pilot Program. Four decades removed from the All-Volunteer Force and Total Force Policy mandate, a significant portion of the US Army's combat power resides in the Army National Guard (ARNG) in terms of brigade combat teams. ARNG brigade combat teams are manned, equipped, and designed to train and deploy as "One Army" with the Active Regular Army for major combat operations. Over the last four decades, numerous opportunities existed for the President, the Department of Defense (DOD), and the US Army to mitigate strategic risk and mobilize ARNG combat brigades for major combat operations, specifically the Persian Gulf War and the Iraq War. To date, numerous challenges prevented their consideration, most notable their inability to meet all peacetime readiness, integration, and responsiveness expectations for major combat operations. In 2016, the US Army announced the new Associated Units Pilot Program to increase readiness, integration, and responsiveness of the ARNG to train and deploy as "One Army" with the Active Regular Army. This monograph asked whether the Associated Units Pilot Program represented a new operational approach for ARNG brigade combat teams and major combat operations. The historical record revealed that it was not only not new, but an old operational approach that failed. The Congress, the DOD, the US Army, and the ARNG stopped challenging assumptions and asking hard questions. ARNG brigade combat teams are no more ready, integrated, or responsive for major combat operations than they were for the Persian Gulf War twenty-six years ago. Most importantly, what is an appropriate operational approach for integrating the peacetime "One Army" for wartime contingencies? What is an appropriate operational approach for General Milley's worst case scenario, major combat operations with a near peer, military competitor? Is the Associated Units Pilot Program a new operational approach, particularly for combined arms units in major combat operations? What are the historical challenges preventing readiness, integration, and responsiveness of "One Army" combined arms units for major combat operations? For brevity, this monograph attempts to answer these questions by focusing on the ability of ARNG combat brigades or brigade combat teams (BCT) to augment the Active Regular Army for major combat operations.