Rear Admiral Michael Day became Acting Deputy Commandant for Mission Support in February 2025. As Deputy Commandant for Mission Support, Rear Admiral Day leads the 17,000-person organization that delivers the people and systems that enable the U.S. Coast Guard to effectively perform its operational missions; Rear Admiral Day’s responsibility extends to all facets of mission support including the oversight of the recruitment, development, and retention of human capital, the acquisition of complex surface, aviation, C4IT systems, and the overall lifecycle engineering and logistics required to maintain and support Coast Guard assets, infrastructure, information technology, and security.

Prior to this role, Rear Admiral Day served as the Director of Talent Management Transformation Program Integration Office. Rear Admiral Day has served as Commander of the Fourteenth Coast Guard District, where he played a key role in strengthening maritime governance and international cooperation in the Indo-Pacific region. He oversaw operations in Oceania, including Hawai’i, Guam, American Samoa, and parts of Asia.

Rear Admiral Day has served in the Strategy and Policy Directorate (J5) for the Chairman of the Joint Chiefs of Staff, as Military Advisor to the Secretary of Homeland Security, and in several significant leadership positions, including Executive Assistant to the Commandant and Vice Commandant, Commander of Sector New York, and Commanding Officer of the Pacific Strike Team.

Notably, Rear Admiral Day was the on-scene commander during the Coast Guard’s response to the 9/11 attacks, where he coordinated the evacuation of more than 500,000 people from Lower Manhattan—the largest maritime evacuation in history.

Rear Admiral Day holds a graduate degree in National Security and Strategic Studies from the Naval War College and a Master of Public Administration from Bridgewater State University. He also completed a fellowship at Harvard University’s Kennedy School of Government. Rear Admiral Day has received numerous military and civic awards, though he finds the awards tied to unit performance most rewarding, as they reflect the collective achievements of the entire crew.