Under Secretary of the Navy Hung Cao has been named Acting Secretary of the Navy effective immediately, the Pentagon announced on April 22, 2026, following the departure of Secretary of the Navy John C. Phelan.
“Secretary of the Navy John C. Phelan is departing the administration, effective immediately,” Chief Pentagon spokesman Sean Parnell posted on X. “On behalf of the Secretary of War and Deputy Secretary of War, we are grateful to Secretary Phelan for his service to the Department and the United States Navy. We wish him well in his future endeavors. Undersecretary Hung Cao will become Acting Secretary of the Navy.”
Hung Cao, who was confirmed as Under Secretary of the Navy in October 2025, serves as the Department of the Navy’s Chief Operating Officer and Chief Management Officer. A retired Navy captain and combat veteran, Cao is a qualified Special Operations, Explosive Ordnance Disposal, Diving, and Surface Warfare Officer. He immigrated to the United States as a Vietnamese refugee in 1975 and is a Naval Academy graduate.
The Pentagon provided no reason for Phelan’s abrupt departure in its official statement. Phelan had spoken at the Navy League’s Sea, Air, Space conference the day prior.
According to a report by Politico, Phelan’s support for a costly new “Trump Class” battleship program had created tensions with Defense Secretary Pete Hegseth and Deputy Secretary Stephen Feinberg, who favored a shift toward smaller, uncrewed vessels. The article also noted that Phelan had recently seen some responsibilities shifted away from his office.