Navy Secretary John Phelan Abruptly Resigns Amid Pentagon Shake-Up; Hung Cao Named Acting Secretary

WASHINGTON — The Pentagon announced Wednesday that Navy Secretary John Phelan has resigned effective immediately, marking the first service secretary departure during President Donald Trump’s second term and the latest high-level exit amid a broader leadership shake-up at the Defense Department.

Immediate Departure, No Public Explanation

No reason was provided for Phelan’s sudden exit. The announcement comes as the Navy has imposed a blockade on Iranian ports and is targeting vessels linked to Tehran while a fragile cease-fire remains in place. Pentagon spokesman Sean Parnell posted on X that Phelan was "departing the administration, effective immediately."

Acting Secretary Named

Undersecretary Hung Cao, a Trump ally and a 25-year Navy combat veteran, will serve as acting secretary. Cao previously ran unsuccessful Republican campaigns for the U.S. Senate and House in Virginia and was endorsed by President Trump in his 2024 Senate primary.

FILE - Hung Cao speaks during the Republican National Convention, July 16, 2024, in Milwaukee. (AP Photo/Matt Rourke, file)(ASSOCIATED PRESS)

Context: A Series Of Pentagon Personnel Changes

Phelan’s exit adds to a string of high-profile removals and resignations at the Pentagon under Defense Secretary Pete Hegseth. In recent months Hegseth has dismissed several senior officers, including Gen. Randy George, Adm. Lisa Franchetti and Gen. Jim Slife. President Trump also removed Gen. Charles "CQ" Brown Jr. as chairman of the Joint Chiefs of Staff.

Phelan’s Background

Phelan had no prior military service or earlier civilian leadership role within the Navy before his nomination in late 2024. A major donor to Trump’s campaign, he founded the private investment firm Rugger Management LLC. His public ties to defense issues included an advisory role with Spirit of America, a nonprofit that supported efforts to aid Ukraine and Taiwan.

Cao’s Record And Controversies

Cao fled Vietnam as a child and later graduated from Thomas Jefferson High School for Science and Technology before attending the U.S. Naval Academy. He served as a special operations officer with SEAL teams and special operations forces in Iraq, Afghanistan and Somalia, retiring at the rank of captain. He also holds a master’s degree in physics and completed fellowships at MIT and Harvard, according to his campaign biography.

FILE - John Phelan appears before a Senate Committee on Armed Services hearing on Capitol Hill, Feb. 27, 2025, in Washington. (AP Photo/Rod Lamkey, Jr., file)(ASSOCIATED PRESS)

During his 2024 Senate campaign, Cao criticized COVID-19 vaccine mandates for service members and denounced diversity, equity and inclusion programs in the military. In a debate with Sen. Tim Kaine, Cao made a controversial remark about recruitment and military culture that drew national attention.

Operational Environment

Phelan leaves while the Navy is operating at high tempo: three aircraft carriers are reported to be deployed or en route to the Middle East, and the service has sustained operations in the Caribbean, including strikes against suspected drug-smuggling vessels. The administration has warned that U.S. forces are prepared to resume combat operations against Iran if the cease-fire collapses.

Next Steps

Acting Secretary Cao will lead the Navy while the administration determines a permanent successor. The Associated Press and other outlets reported they were unable to immediately reach Phelan for comment, and the White House directed inquiries to the Pentagon statement.

Statement: "John Phelan is departing the administration, effective immediately." — Pentagon spokesman Sean Parnell (posted on X)