This photograph from the Edward P. McAleer collection depicts a staged gas mask and casualty-response training exercise, likely conducted at a U.S. Army post during World War II. Soldiers regularly drilled in chemical warfare defense procedures, including donning protective masks and rendering aid to a simulated casualty, in preparation for the possibility of gas attack, a persistent fear carried over from World War I. Images such as this document the routine, often overlooked training that shaped American soldiers before deployment overseas. Project: 218143