President Donald Trump’s administration has seen another high-profile departure from its national security team, with Navy Secretary John Phelan leaving his post amid reported tensions with senior Pentagon leadership. The abrupt announcement came just weeks after Defense Secretary Pete Hegseth dismissed the Army’s top uniformed officer, continuing a pattern of leadership changes within the Defense Department.
Phelan, a former private investment fund manager from Florida and a Trump donor, was confirmed as Navy secretary in early 2025. His removal marks the first departure of a military service secretary during Trump’s second term, according to Pentagon officials. Undersecretary Hugh “Hung” Cao, a 25-year Navy combat veteran, has assumed the role of acting Navy secretary following Phelan’s exit.
The Pentagon offered no specific reason for Phelan’s departure when it announced the change on Wednesday. However, multiple news outlets have reported that the decision stemmed from interpersonal conflicts and policy disagreements, particularly regarding the pace of shipbuilding initiatives.
Reports indicate that Phelan’s relationship with Defense Secretary Pete Hegseth had deteriorated over several months. Sources cited by The Guardian noted tensions with Deputy Secretary of Defense Steve Feinberg and even Phelan’s own deputy, Hugh Cao. These interpersonal strains were described as long-standing and had reportedly hindered effective collaboration within the Navy’s leadership structure.
Beyond personal dynamics, policy disagreements appear to have played a significant role. According to sources familiar with the situation, there was growing concern within the Pentagon that Phelan was not moving quickly enough on shipbuilding reforms that President Trump had personally advocated. Feinberg, in particular, was said to have sought greater control over Navy shipbuilding and major acquisition programs, a goal that sources indicate he ultimately achieved amid the leadership transition.
The timing of Phelan’s removal coincided with heightened regional tensions, including an ongoing naval blockade of Iranian ports and increased maritime interdiction efforts targeting vessels linked to Tehran. Despite these operations, officials emphasized that the leadership change was unrelated to the conduct of ongoing military actions in the Middle East.
Phelan’s departure follows a broader trend of senior military and defense officials leaving their posts since Hegseth assumed office. In February 2025, Hegseth removed several high-ranking officers, including Admiral Lisa Franchetti, the Navy’s top uniformed officer, and General Jim Slife, the vice chief of staff of the Air Force. More recently, Chairman of the Joint Chiefs of Staff General Charles “CQ” Brown Jr. Was also dismissed.
These successive removals have raised questions about the stability of military leadership under the current administration. Defense analysts note that such rapid turnover at the highest levels of the Department of Defense could impact long-term planning and inter-service coordination, particularly during periods of active overseas engagements.
Hugh Cao, now serving as acting Navy secretary, brings a distinct background to the role. Born in Vietnam and raised as a refugee in the United States, Cao enlisted in the Navy and served for over two decades, including combat deployments. He later pursued political office, running unsuccessfully for both the U.S. Senate and House of Representatives in Virginia as a Republican candidate.
Cao has previously spoken publicly about his vision for the military, advocating for a force composed of what he described as “alpha males and alpha females.” These remarks, made prior to his appointment as acting secretary, have drawn attention for their emphasis on assertiveness and competitiveness within military culture.
As the administration continues to reshape its national security leadership, the implications of these changes remain under close scrutiny. With no permanent successor yet nominated for the Navy secretary position, Cao’s tenure as acting secretary may extend for several months unless and until a formal nomination is made and confirmed by the Senate.
For ongoing updates on Defense Department leadership and policy developments, readers are encouraged to consult official announcements from the U.S. Department of Defense and verified reporting from reputable news sources.