Cooke had a federal government career of more than 45 years in the Pentagon from 1957 to 2002. Notable positions he served in include Deputy Assistant Secretary of Defense for Administration from 1971 to 1988, Director of the Washington Headquarters Services since 1977, and Director of Administration and Management in the Office of the Secretary of Defense since 1988.
Cooke was involved with Defense Department management issues since 1958, when he served on Defense Secretary Neil McElroy's task force on Department of Defense reorganization. He served under Defense Secretary Robert McNamara and helped institute changes in departmental management. Following his Navy retirement, Cooke headed the Department's Office of Organizational and Management Planning, a job that evolved into his final post. In this position, Cooke was responsible for the physical plant and personnel administration of the Pentagon. His responsibilities for security, maintenance, and operations in the building earned him the title "Mayor" - the phrase "Mayor of the Pentagon" had often been used to refer to him during his tenure,[3] a nickname that continued to be used for those who held the position after him, including Raymond F. DuBois.[4]
On June 22, 2002, Cooke died from injuries that were a result of a car accident on June 6. He is buried at Arlington National Cemetery in Virginia, overlooking the Pentagon. His wife of 52 years, Marion McDonald Cooke, died in 1999. The couple had raised three children, Michele C. Sutton of Springfield, David Cooke and Lot Cooke, both of Fairfax. He also had two grandchildren at the time of his death. Elizabeth M. Cooke, who was born in 2000, and David B. Cooke who was born in 2002 a week before Cooke's death (both children from David O. Cooke Jr.).
In 2005, the "David O. Cooke Excellence in Public Administration Award" was established in Cooke's honor to recognize a DoD employee with three to 10 years of federal service who occupies a non-managerial position and exhibits great potential as a future federal executive.
^"David O. Cooke". Hearings Regarding the Administration of the Subversive Activities Control Act of 1950 and the Federal Civilian Employee Loyalty-security Program: Hearings, Ninety-first Congress, Second Session [and Ninety-second Congress, First Session], Part 3. U.S. Government Printing Office. 1971. p. 2718. Retrieved 2021-10-10.