US Navy Secretary John Phelan has left the Trump administration with immediate effect, in the latest senior level shakeup at the Pentagon. Pentagon spokesman Sean Parnell announced the move on Wednesday and said Navy Undersecretary Hung Cao will serve as acting secretary. No official reason was given for Phelan’s departure.
Reuters reported that Phelan was dismissed, citing a source familiar with the matter, while the Pentagon’s public statement described the move only as a departure. Reuters said the exit followed tensions over shipbuilding reforms and strained relationships with senior Pentagon officials, including Defense Secretary Pete Hegseth and Deputy Defense Secretary Steve Feinberg. Reuters also reported that Phelan had been facing an ethics probe.
Phelan was a civilian businessman and major Trump donor who had not previously served in the military. He became Secretary of the Navy in March 2025, entering office as an outsider at a time when the administration was pushing for major reforms in US shipbuilding and naval expansion.
His departure comes during a period of wider upheaval inside the Defense Department. Reuters reported earlier this month that Hegseth had asked Army Chief of Staff Randy George to step down, and that Gen. David Hodne and Maj. Gen. William Green were also removed from their posts. Reuters also said Hegseth had already overseen other high profile departures, including the chairman of the Joint Chiefs of Staff and top Air Force and Navy officers.
The leadership change also comes at a sensitive moment for US naval operations. The Navy has been central to US activity linked to the blockade around Iran and the broader confrontation in and around the Strait of Hormuz, where shipping tensions remain high even amid ceasefire efforts. AP said Phelan’s exit happened as the Navy was playing a key role in blockades of Iranian ports and wider maritime monitoring.
Phelan’s replacement, Hung Cao, brings military experience to the role. AP described him as a former Navy SEAL and said he has aligned closely with Trump era defense priorities. Reuters and other reports identify him as the Navy’s undersecretary before this appointment, and he now steps in as acting secretary at a time of intense pressure on the service.
The change is likely to fuel more scrutiny of instability at the Pentagon, especially as the administration tries to accelerate naval expansion and manage wartime demands. For now, the Pentagon has offered no public explanation beyond thanking Phelan for his service and confirming that the transition is already in effect.
One small correction to the pasted draft: the Pentagon statement thanked him on behalf of the Secretary of Defense, not “Secretary of War,” which is not the current US cabinet title. That appears to be an error in the source text rather than the official wording.
