This study analyzes the operational performance of the 28th Infantry Division during a period of high intensity combat in the European Theater of Operations. The focus is on the difficulties the division experienced within its subordinate infantry units. Infantrymen, though comprising less than 40 percent of the division's total strength, absorbed almost 90 percent of all casualties. The high casualty rate within infantry units severely curtailed the operational performance of the division. The difficulties the 28th experienced were commonplace in the European theater. Compounding the problem was the inadequate number of divisions in the U.S. Army force structure. This inadequacy forced divisions to remain in combat for excessive durations, greatly increasing battle and non-battle casualties. The army's personnel system further contributed to the problems infantry divisions experienced within their infantry units. It failed to provide sufficient numbers of infantry replacements in a timely manner and there was widespread dissatisfaction with the quality of infantry replacements. This study shows that the U.S. Army failed to realize both the importance of infantry units to the war effort and the severity of combat on the modern battlefield. The result was an infantry force structure poorly designed to accomplish its wartime mission.