The firing of US Navy Secretary John Phelan is the latest in a shakeup of the American military during the war on Iran, now in its eighth week.

The Pentagon said Phelan would leave office immediately.

“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,” said chief Pentagon spokesperson Sean Parnell. “We wish him well in his future endeavours”.

His firing comes at a critical moment, with US naval forces enforcing a blockade on Iranian ports and ships, and maintaining a heavy presence around the Strait of Hormuz, through which 20 percent of the world’s oil and gas passes during peacetime.

Although the Pentagon gave no official reason for the dismissal, reports indicate the decision was linked to internal disputes, including tensions with Defense Secretary Pete Hegseth.

Phelan’s removal is part of a broader pattern of dismissals and restructuring within the US military under President Donald Trump’s administration – including during the current war.

So, who is John Phelan, and what impact could his firing have on US military strategy?

Who is John Phelan?

As the US Navy’s top civilian official, Phelan had various responsibilities, including overseeing recruiting, mobilising and organising, as well as construction and repair of ships and military equipment.

He was appointed in 2024 as a political ally of Trump, despite having no prior military or defence leadership experience.

Before entering government, Phelan was a businessman and investment executive, as well as a major Republican donor and fundraiser — a background that is fairly common among Trump appointees and advisers. The US president’s two top diplomatic negotiators, for instance, are Steve Witkoff — a real estate businessman with no prior diplomatic experience – and Trump’s son-in-law, Jared Kushner.

According to the Reuters news agency, Phelan’s tenure quickly became controversial. He faced criticism for moving too slowly on shipbuilding reforms and for strained relationships with key Pentagon figures, including Hegseth and his deputy, Steve Feinberg.

In addition, Phelan was reportedly under an ethics investigation, which may have weakened his standing in the administration.

Navy Undersecretary Hung Cao, who was also reported to have a difficult relationship with Phelan, has become acting secretary. Fifty-four-year-old Cao is a 25-year Navy veteran who previously ran as a Republican candidate for the US Senate and House of Representatives in 2022 and 2024 respectively, but was unsuccessful on both occasions.

Democrats have criticised Phelan’s removal, calling it “troubling”.

“I am concerned it is yet another example of the instability and dysfunction that have come to define the Department of Defense under President Trump and Secretary Hegseth,” said Senator Jack Reed, the top Democrat on the Senate Armed Services Committee.

Who else has the Trump administration fired since the war with Iran began?

Phelan’s removal is the latest in a series of senior military leaders being fired or are leaving during the US-Israeli war on Iran, in addition to others since Trump was re-elected.

Among the most notable dismissals was Army Chief of Staff General Randy A. George, in the first week of April. George was appointed in 2023 under former US President Joe Biden.

According to reports, Hegseth also fired the head of the Army’s Transformation and Training Command, a unit concerned with modernising the army, and the Army’s chief of chaplains. The Pentagon has not confirmed their dismissal.

Why is Phelan’s dismissal significant?

The 62-year-old’s removal comes during a fragile ceasefire with Iran, as the ⁠⁠US continues to move more naval assets into the region.

The Navy is central to enforcing Trump’s blockade of Iranian ports to restrict Iran’s oil exports and apply economic pressure on Tehran, as the US president looks eager to wrap up the war, which is deeply unpopular to many Americans.

However, there are no indications that Trump is willing to end the blockade or other naval operations in the Strait of Hormuz, as negotiations between Washington and Tehran have come to a standstill.

Tensions have escalated in recent days after the US military seized an Iranian container ship. The US claimed it was attempting to sail from the Arabian Sea through the Strait of Hormuz to the Iranian port of Bandar Abbas.

Tehran responded by describing the attack and hijack as an act of “piracy”.

Iran has since captured two cargo ships and fired at another.

WASHINGTON — Navy Secretary John Phelan is leaving his job, the Pentagon abruptly announced Wednesday, the first head of a military service to depart during President Trump’s second term but just the latest top defense leader to step down or be ousted.

No reason was given for the unexpected departure of the Navy’s top civilian official, coming as the sea service has imposed a blockade of Iranian ports and is targeting ships linked to Tehran around the world during a tenuous ceasefire in the war. Another Trump loyalist is taking over as acting head of the Navy: Undersecretary Hung Cao, a 25-year Navy combat veteran who ran unsuccessful campaigns for the U.S. Senate and House in Virginia.

Phelan’s departure is the latest in a series of shakeups of top leadership at the Pentagon, coming just weeks after Defense Secretary Pete Hegseth fired the Army’s top uniformed officer, Gen. Randy George. Hegseth also has fired several other top generals, admirals and defense leaders since taking office last year.

The firings began in February 2025, when Hegseth removed military leaders, including Adm. Lisa Franchetti, the Navy’s top uniformed officer, and Gen. Jim Slife, the No. 2 leader at the Air Force. Trump also fired Gen. Charles “CQ” Brown Jr. as chairman of the Joint Chiefs of Staff.

Showing how sudden the latest move was, Phelan had addressed a large crowd of sailors and industry professionals on Tuesday at the Navy’s annual conference in Washington and spoke with reporters about his agenda. He also hosted the leaders of the House Armed Services Committee to discuss the Navy’s budget request and efforts to build more ships, according to a social media post from his office.

Pentagon spokesman Sean Parnell said in a post on X that Phelan was “departing the administration, effective immediately.”

Phelan had been a major Trump donor

Phelan had not served in the military or had a civilian leadership role in the service before Trump nominated him for secretary in late 2024. He was seen as an outsider being brought in to shake up the Navy.

Hung Cao speaks during the Republican National Convention on July 16, 2024, in Milwaukee.

Matt Rourke/AP

Advertisement

hide caption

toggle caption

Matt Rourke/AP

Advertisement

Phelan was a major donor to Trump’s campaign and had founded the private investment firm Rugger Management LLC. According to his biography, Phelan’s primary exposure to the military came from an advisory position he held on the Spirit of America, a nonprofit that supported the defense of Ukraine and the defense of Taiwan.

The Associated Press could not immediately reach Phelan’s office for comment. The White House did not answer questions and instead responded by sending a link to Parnell’s statement.

Phelan is leaving during a busy time for the Navy. It has three aircraft carriers deployed in or heading to the Middle East, while the Trump administration says all the armed forces are poised to resume combat operations against Iran should the ceasefire expire.

The Navy also has maintained a heavy presence in the Caribbean, where it has been part of a campaign of strikes against alleged drug boats. It also played a major role in the capture of Venezuelan leader Nicolás Maduro in January.

New acting Navy secretary ran unsuccessful bids for Congress

Taking over as acting secretary is Cao, who ran a failed U.S. Senate bid in Virginia to try to unseat Democratic Sen. Tim Kaine in 2024. He had Trump’s endorsement in the crowded Republican primary and gave a speech at the 2024 Republican National Convention.

Cao’s biography includes fleeing Vietnam with his family as a child in the 1970s. In a campaign video for his Senate bid, he compared Vietnam’s communist regime during the Cold War to the administration of Democratic President Joe Biden.

During his one debate with Kaine, Cao criticized COVID-19 vaccine mandates for service members as well as the military’s diversity, equity and inclusion efforts.

“When you’re using a drag queen to recruit for the Navy, that’s not the people we want,” Cao said from the debate stage. “What we need is alpha males and alpha females who are going to rip out their own guts, eat them and ask for seconds. Those are the young men and women that are going to win wars.”

Trump and Hegseth have railed against DEI in the military, banning the efforts and firing people accused of supporting such programs.

When he ran for Congress in Virginia in 2022, Cao expressed opposition to aid for Ukraine during a debate against his Democratic opponent.

“My heart goes out to the Ukrainian people. … But right now we’re borrowing $55 billion from China to pay for the war in Ukraine. Not only that, we’re depleting our national strategic reserves,” Cao said.

Cao graduated from the prestigious Thomas Jefferson High School for Science and Technology in Alexandria, Virginia, before attending the U.S. Naval Academy.

He was commissioned as a special operations officer and went on to serve with SEAL teams and special forces in Iraq, Afghanistan and Somalia before retiring at the rank of captain, according to his Senate campaign biography.

Cao also earned a master’s degree in physics and had fellowships at the Massachusetts Institute of Technology and Harvard University.

Since becoming Navy undersecretary, Cao has championed returning to duty service members that refused a Biden-era mandate to take the COVID-19 vaccine.