He was commissioned a second lieutenant in 1962 following completion of the Platoon Leaders Class program.

His staff tours included Deputy Director, J-3, U.S. European Command as well as Deputy Chiefs of Staff for Requirements and Programs, and Aviation at Headquarters Marine Corps, Washington, D.C. General Hearney was advanced to general and assumed the position of assistant commandant on July 15, 1994.

General Hearney currently sits on the Honorary Board for the 501 (c) (3) Non Profit Wine Country Marines [1] In the 2024 United States presidential election, Hearney endorsed Kamala Harris.

His personal decorations and medals include:  This article incorporates public domain material from websites or documents of the United States Marine Corps.

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