The abrupt dismissal of National Security Adviser Mike Waltz has intensified the internal power struggle within President Donald Trump’s White House, as ideological tensions deepen between traditional Republican hawks and the isolationist wing of the administration.
Waltz’s removal, announced Thursday, sets off another shake-up in the national security team just days after Trump reached the 100-day milestone of his second term.
Waltz, a former congressman and decorated Army officer known for his hawkish views on foreign policy, will be nominated to serve as the United States ambassador to the United Nations, Trump said in a brief statement.
In the meantime, Secretary of State Marco Rubio will assume the additional role of national security adviser, temporarily consolidating two of the administration’s most important foreign policy positions in one figure.
The decision to remove Waltz follows a turbulent period inside the White House, during which he faced increasing criticism from hardline Trump loyalists. The final blow appeared to be a combination of mounting friction with other key members of the administration and his central role in a controversy involving encrypted Signal messages sent among top officials in March.
Waltz’s departure comes on the heels of a broader purge within the national security apparatus. In recent weeks, top officials at the National Security Council and the National Security Agency have been fired or forced out.
The Pentagon, meanwhile, remains mired in a separate scandal involving internal leaks and rising pressure on Defense Secretary Pete Hegseth, who faces scrutiny over his handling of classified information and management of senior staff.
Senator Jeanne Shaheen of New Hampshire, the top Democrat on the Senate Foreign Relations Committee and a senior voice on military issues, reacted sharply to Waltz’s removal.
“Mike Waltz’s abrupt dismissal is further proof of the chaos and incompetence that has reigned over President Trump’s White House and national security team during his first 100 days in office,” Shaheen said in a statement. “The stunning amount of turnover of senior staff at both the National Security Council and at the Pentagon is alarming.”
While the U.N. ambassadorship could serve as a high-profile international platform, the reassignment removes Waltz from Trump’s inner circle and the daily operations of foreign policy decision-making. Some Republican lawmakers expressed disappointment at the change, though few were willing to challenge Trump’s decision directly.
“He did a very good job as national security adviser,” said Senator Ted Cruz of Texas. “It’s the prerogative of the president to decide who his team will be, but I was sorry to see that news.”
For traditional conservatives who still value long-standing U.S. alliances and assertive foreign policy, the news was troubling. Waltz has been considered a key internal counterweight to the more nationalist and isolationist voices in Trump’s orbit.
His influence, though quiet, was believed to have blocked several controversial proposals from advancing further.
“We’ll never know what outrageous proposals made their way to Waltz’s desk en route to the Oval Office and were quietly blocked thanks to him,” said a foreign policy analyst at a conservative think tank, speaking on condition of anonymity to preserve working relationships.
“While Rubio’s interim appointment is comforting, who President Trump picks to replace Waltz full time will say a lot about the future direction of this White House’s foreign policy.”
The controversy surrounding Waltz escalated in March when The Atlantic revealed that he had accidentally added the magazine’s editor, Jeffrey Goldberg, to a private Signal chat between top national security officials.
In that chat, Waltz pushed back against claims made by Defense Secretary Hegseth and Vice President J.D. Vance that the United States was being manipulated by European powers to take action in the Red Sea region. At the time, the administration was considering additional military operations to secure shipping lanes near Yemen.
“So whether it’s now, or several weeks from now, it will have to be the United States that reopens these shipping lanes,” Waltz wrote in the thread, defending a more active American role.
The leak from the chat became a public embarrassment and prompted calls for greater scrutiny of how senior officials were communicating. But insiders suggest that the chat scandal was not the decisive factor in Waltz’s removal.
Rather, it was his deteriorating relationships with key Trump allies, including Chief of Staff Susie Wiles, Vice President Vance, and senior adviser Steve Witkoff, that led to his exit.
According to reporting from Axios and other sources, Waltz had grown increasingly isolated within the White House, particularly as MAGA-aligned staffers sought to elevate figures more aligned with Trump’s America First vision.
Meanwhile, Rubio’s expanded role is being viewed as a stabilizing choice in an otherwise chaotic landscape. The secretary of state has built a strong rapport with the president, managing to avoid direct clashes with Trump’s more disruptive allies while still advocating for traditional foreign policy approaches.
Rubio’s appointment comes after he successfully led a reorganization of the State Department, avoiding the steep budget cuts proposed by Elon Musk’s Department of Government Efficiency. During a recent Oval Office meeting, Trump reportedly defended Rubio from criticism by Musk, saying, “Marco’s doing a good job.”
That endorsement followed a public moment of praise during a Cabinet meeting earlier this week, where Trump was seen patting Rubio’s hand after the secretary concluded his remarks. Though largely symbolic, the gesture signaled Trump’s confidence in Rubio and his growing stature within the administration.
“He is someone who is well known by the president,” said State Department spokesperson Tammy Bruce. “The president makes perfect assessments of who would implement his agenda, and in this case he’s chosen certainly the secretary, and Mr. Waltz to facilitate his agenda moving forward. Not entirely surprising, I have to say, and good news for the American people.”
Still, the question of who will permanently replace Waltz remains unanswered, and speculation is swirling about possible nominees. Some White House watchers expect Trump to select someone with closer ideological ties to his nationalist supporters, a move that could shift foreign policy further toward isolationism and away from international engagement.
Democratic lawmakers wasted no time in using the shake-up to renew calls for the removal of Defense Secretary Hegseth, whose own position has become increasingly precarious amid ongoing investigations.
“Waltz is out. Hegseth, you’re next,” posted Representative Ted Lieu of California, a Democrat and member of the House Foreign Affairs Committee.
With the national security apparatus undergoing such rapid turnover, some observers fear that institutional memory and strategic coherence may be lost in the shuffle. Others see the changes as an opportunity for Trump to consolidate power among loyalists more aligned with his vision for the United States’ role in the world.
What remains clear is that Trump’s national security team is undergoing a period of major transition, with consequences yet to be fully understood. Rubio’s expanded responsibilities may offer temporary steadiness, but all eyes are now on who will permanently take over one of the most sensitive and influential roles in the executive branch.
For now, the removal of Waltz underscores an ongoing theme of Trump’s second term — loyalty, above all, is what determines survival in his administration. Whether the next national security adviser shares that loyalty, and what that means for U.S. foreign policy, will soon become clear.
