Player Embed Code: Download Embed Share Defense Leaders Testify at Senate on Conclusion of Military Operations in Afghanistan, Part 3 Defense.gov Sept. 28, 2021 | 49:59 Secretary of Defense Lloyd J. Austin III; Army Gen. Mark A. Milley, chairman of the Joint Chiefs of Staff; and Marine Corps Gen. Kenneth F. McKenzie Jr., commander of U.S. Central Command, provide testimony on the conclusion of military operations in Afghanistan and plans for future counterterrorism operations.