The focus of this thesis is to determine how U.S. Army corps and divisions ensure deliberate gap crossings, a type of combined arms operations, are planned using operational art. Examination of doctrine for gap crossings shows gap crossing to be tactical problems. Corps, division, and operational art doctrine does not directly address the need to incorporate gap crossings as part of an overall campaign. This paper compares two case studies from World War II in their strategic context with tactical outcomes using operational art. The failed crossing of the Rapido River in Italy and the...