John Samuel Kem (born 1963) is a retired United States Army major general who last served as the 51st Commandant of the United States Army War College at Carlisle Barracks from July 28, 2017, to July 30, 2020. He previously served as the 1st provost of the Army University while dual-hatted as the deputy commanding general for education of the United States Army Combined Arms Center and deputy commandant of the United States Army Command and General Staff College. He was promoted to major general on October 3, 2016.

Kem earned his commission through a bachelor's degree in civil engineering from the United States Military Academy in 1985. He also holds a master's degree in Environmental Engineering and a master's degree in business administration from Northwestern University, the latter from its Kellogg Business School. He is a Chartered Financial Analyst and registered professional engineer in Virginia, where he resides in Annandale as of his retirement.

Military offices
Preceded byAnthony C. FunkhouserCommanding General of the Northwestern Division of the United States Army Corps of Engineers 2013-2015Succeeded byScott A. Spellmon
New officeProvost of the Army University and Deputy Commandant of the United States Army Command and General Staff College 2015-2017Succeeded byScott L. Efflandt
Preceded byWilliam E. RappCommandant of the United States Army War College 2017-2020Succeeded byStephen J. Maranian