The statement was made late on a Wednesday night in the kind of social media post that has grown to be the go-to source for unplanned Pentagon news. The principal spokesperson for the Defense Department, Sean Parnell, announced on X that Navy Secretary John C. Phelan would “departing the administration, effective immediately” and that Undersecretary Hung Cao would assume an acting role.
No explanation was provided. No press conference. No timeline for the transfer. In the midst of an ongoing blockade of Iranian ports, the U.S. Navy had subtly replaced its civilian leadership by the time the majority of Washington had seen the piece and considered its implications.
| New Navy Secretary — Key Information | Details |
|---|---|
| Acting Secretary | Hung Cao |
| Age | 54 |
| Previous Role | Under Secretary of the Navy |
| Date Promoted | April 22, 2026 |
| Predecessor | John C. Phelan (fired) |
| Reason for Phelan’s Removal | Slow shipbuilding reform; chain-of-command tensions with Hegseth |
| Defense Secretary | Pete Hegseth |
| Operational Backdrop | U.S. naval blockade of Iranian ports |
| Cao’s Naval Career | 25 years, retired Navy captain |
| Cao’s Specialty | Diving and explosive ordnance disposal |
| Combat Tours | Iraq and Afghanistan |
| Vietnamese Origin | Family fled Vietnam as refugees in the 1970s |
| Political Background | Failed U.S. Senate bid (2024), House run (2022) |
| Stated Priority | Shipbuilding acceleration |
| Reference Reporting | USNI News |
Reports over the next few days revealed that the firing’s mechanics were more precise than the official account said. According to CNN, after months of conflict, Defense Secretary Pete Hegseth became irritated with Phelan because he thought he was too forthright in his interactions with President Trump and too slow on shipbuilding reform. During a brief meeting in the Oval Office, the president instructed Hegseth to “take care of it.” Then Hegseth messaged Phelan, threatening to dismiss him if he didn’t quit.
One particular detail in the story perfectly depicts the peculiarity of the situation: Phelan started phoning other White House officials to get confirmation, seemingly unsure if Trump was aware of the demand. Eventually, he personally went to the West Wing in search of the president, who had a quick meeting with him to corroborate the information.
In significant aspects, Cao’s route to the acting secretaryship is unique. He served as a special operations diver in Iraq and Afghanistan, escaped Vietnam with his family as a teenager in the 1970s, and held a budget programming position in the Office of the Chief of Naval Operations at the Pentagon. He is a 25-year Navy combat veteran. He left the Navy as a captain, lost a 2024 Senate campaign in Virginia to Tim Kaine, and made an unsuccessful run for the U.S. House in 2022.
He gave a speech during the Republican National Convention in 2024. He is the type of person who, by conventional career criteria, usually ends up in a senior Defense Department position rather than at the top of a service. That math was altered overnight by Phelan’s abrupt departure.
According to most accounts, Cao and Phelan had a tense relationship. According to those who spoke to CNN, Phelan effectively kept Cao “in a box” and prevented him from representing the Secretary at meetings that Phelan himself did not attend. The dynamic was important. The Pentagon front office reportedly told Cao, “Ok, you’re it — we made a change,” when he learnt of his elevation. He then had to rush to catch up on portfolios from which he had been excluded for months. Reading the story gives the impression that Cao took over not only a challenging position but also a working relationship that had been purposefully kept strained until it was up to him to manage.
It was hard to ignore the operational stakes when strolling through the Pentagon during the week of the handover. During the continuous blockade of Iranian trade, U.S. Navy forces had boarded two ships and rerouted 31 vessels to return to port. There were three aircraft carriers in the Middle East or on their way there. At the same time, the Navy was conducting operations in the Caribbean related to both wider regional positioning and drug interdiction. The Pentagon rarely takes the choice to replace a service’s civilian leadership in the midst of that operational tempo lightly. The fact that it occurred nonetheless reveals how strained Hegseth and Phelan’s relationship had grown.
over five days after his promotion, Cao made his first public remarks as acting secretary over shipbuilding. “I remain fully committed to accomplishing the core mission of the Department of the Navy as a premier warfighting organization and providing unwavering support to our warriors downrange,” he stated. The framing is important. The problem that led to Phelan’s dismissal was shipbuilding. Cao made it apparent to Hegseth and Trump that he understood the directive and planned to act more quickly than his predecessor by bringing it up within days of accepting the position. Given the severe structural problems facing the American shipbuilding sector, the personnel shortages at large shipyards, and the financial constraints associated with the Golden Fleet plan, it is quite another matter entirely whether he can truly fulfill that pledge.
The political signals pertaining to Cao’s permanent confirmation are continuously evolving. Whether Cao will be nominated to serve as Navy secretary indefinitely is unknown. The acting title allows Cao to show that he can advance shipbuilding reform without taking on Phelan’s chain-of-command issues and allows Trump and Hegseth to assess his performance.
The day following the dismissal, Trump strangely complimented Phelan on Truth Social and said that he would like to see him return to the government in the future. The second-term White House is known for its conflicting signals, which include quickly firing someone, publicly praising them, and leaving the door open for their return. The next few months will determine if Cao formally consolidates the role or whether that trend solidifies into a meaningful road back for Phelan.
One of the most unstable portfolios in the Trump administration is the civilian leadership of the Navy, which is difficult to ignore. The barrier is still in place. There is actual strain on shipbuilding. Phelan now joins a list that includes Adm. Lisa Franchetti, Gen. Charles Q. Brown Jr., Gen. Randy George, and several others removed since early 2025.
The Pentagon’s larger pattern of senior leadership turnover suggests that the administration is still actively changing its military leadership in the midst of ongoing operations. Cao takes on a position that is both structurally unstable and highly influential. As this develops, there’s a sense that the person in charge of the Department of the Navy at the end of 2026 might not be the same person in charge today.