2023 U.S. Missile Defender of the Year

Alexandria, VA – January 19, 2024

MDAA brought forward our nation’s very best missile defender from each of the five military services from around the world to be honored and recognized for excellence in leadership in 2023. This leadership of excellence from our Army, Navy, Air Force, National Guard, and Space Force, represented the apex of U.S. missile defense around the world today and put forward under the command of the Commander in Chief, President Joe Biden.

The five honorees, Major Robert Sheehan of the U.S. National Guard, Captain Zachary Buenger of the U.S. Army, Lieutenant Commander Rebekah Fleming of the U.S. Navy, Staff Sergeant John Brannon of the U.S. Air Force, and Sergeant Matthew Critchley of the U.S. Space Force, led from their positions of command and leadership to earn respect, trust, and honor for their actions in operating and further developing the most prominent integrated air and missile defense platforms and systems that have been put in place in the world today.

Sergeant Matthew Critchley
Space Forces Indo-Pacific
Joint Base Pearl Harbor-Hickam, Hawaii
U.S. Space Force


Staff Sergeant John Brannon
603rd Air Operation Center
Ramstein Air Base, Germany
U.S. Air Force


Lieutenant Commander Rebekah Fleming
USS Carney
DDG 64
U.S. Navy


Captain Zachary Buenger
2d Battalion, 44th Air Defense Artillery Regiment
Fort Campbell, Kentucky
U.S. Army


Major Robert Sheehan
164th Air Defense Artillery Brigade
Florida Army National Guard
U.S. National Guard

Major Robert Sheehan, U.S. National Guard

­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­MAJ Sheehan has served as the NCR-IADS Deputy J3 for 4 rotations, and most critically served as a Tactical Director while expertly performing his Deputy J3 duties.  He stands first amongst his peers in knowledge and tenacity and inspires those around him to push the envelope and strive for excellence. He is recognized across the

Captain Zachary Buenger, U.S. Army

CPT Zachary “Zac” Buenger entered the active duty Army in January 2016 after graduating from Colorado School of Mines with a Bachelors of Science degree in Mechanical Engineering. He also possesses a Master’s Degree in Leadership Studies from Marshall University. His military education includes: Air Defense Artillery Basic Officer Leadership Course, U.S. Marine Corps Expeditionary

Lieutenant Commander Rebekah Fleming, U.S. Navy

LCDR Fleming is a native of Angelica, New York. She graduated from the University of Rochester, where she commissioned from the Naval ROTC program with a Bachelor of Arts degree in Psychology in May 2013. She completed her first department head tour as a Weapons Officer aboard USS CARNEY (DDG 64), where she is currently

Staff Sergeant John Brannon, United States Air Force

SSgt Brannon is an Integrated Air and Missile Defense Technician and Senior Air Defense Technician, 603rd Air Operations Center, Ramstein Air Base, Germany. He leads 16 personnel comprising the senior command and control element responsible for 24/7 air and missile defense of 52 EUCOM and AFRICOM countries. The 603d Air Operations Center is the core

Sergeant Matthew Critchley, United States Space Force

Sgt Matthew N Critchley is a Space and Missile Warning Technician in the Space Watch Cell, Space Forces Indo-Pacific, Joint Base Pearl Harbor-Hickam, Hawaii. Sgt Critchley is part of an eight-member team responsible for providing 24/7 theater missile warning and space effects support to the USINDOPACOM Commander. Sgt Critchley is also responsible for ensuring Space

Defenders of the Year