Mike Waltz out: Inside Donald Trump’s sudden shakeup and the scandal that took down his security adviser

US President Donald Trump on Thursday announced the replacement of national security adviser Mike Waltz, stating that he would be nominated as the next ambassador to the United Nations.
In the first major cabinet reshuffle, just over 100 days into his new term, following a string of controversies and internal tensions the President named secretary of state Marco Rubio as interim national security adviser.
"From his time in uniform on the battlefield, in Congress and, as my National Security Advisor, Mike Waltz has worked hard to put our Nation's Interests first," Trump posted on Truth Social while announcing the changes.

"I'm deeply honoured to continue my service to President Trump and our great nation," Waltz responded in a post on X.

Who is Mike Waltz?

Born in Boynton Beach, Florida, Waltz is the son and grandson of Navy chiefs. He was raised by a single mother and is known for his military and national security background.
Before entering politics, he worked in the Pentagon and served in the White House under President George W Bush.
Waltz was elected to Congress in 2018, representing Florida’s 6th District. He became the first Green Beret ever elected to the US House and served on key committees including Intelligence, Armed Services, and Foreign Affairs.
He also joined the House China Task Force and was known for his strong anti-China policies. Trump appointed Waltz as national security adviser in November, praising him as a respected defense expert.

Why Mike Waltz was replaced?

Waltz’s exit came in the wake of the so-called "Signal gate" scandal that erupted in March. The former congressman from Florida and retired Green Beret mistakenly added Atlantic magazine editor Jeffrey Goldberg to a private Signal group chat that included top US security officials.
The group was reportedly discussing sensitive military plans, including potential US airstrikes on Houthi targets in Yemen, according to several reports.
During his final cabinet meeting, Waltz was photographed checking his phone, and a zoomed-in image showed an ongoing Signal conversation with a contact saved as "JD Vance"—the current US Vice President.
The message read: “I have confirmation from my counterpart it’s turned off. He is going to be here in…” It remains unclear whether Waltz or Vance sent the message, the Daily Beast reported.
The leak raised serious concerns about operational security. It also exposed a broader pattern of questionable digital communication among senior officials.
Defense secretary Pete Hegseth is also under scrutiny for allegedly sharing military flight details in another Signal chat that included his wife.
Multiple sources told BBC that Waltz’s handling of the National Security Council staff and the leak were key reasons for his removal.
While Trump publicly supported Waltz, insiders said he had lost confidence in him and wanted a quieter way to remove him. By nominating Waltz to a high-profile role like UN ambassador, Trump avoided the optics of firing him outright, the outlet added.

Despite the abrupt end to his tenure, Vance insisted the move to the UN post was a promotion and had nothing to do with the Signal controversy.
Still, Democrats are calling for further accountability. Senate majority leader Chuck Schumer has urged action against Defense Secretary Hegseth, tweeting: “Now do Hegseth.”
Waltz’s 101-day stint as national security adviser is now the second-shortest in US history—just behind Michael Flynn’s three-week tenure in Trump’s first term.