By Tarini Parti and Alex Leary

WASHINGTON -- President Trump expressed support for his national security adviser and the White House denied that classified materials were shared by administration officials on a group chat on a nongovernment service that mistakenly included a journalist.

The Atlantic's report has put a spotlight on national security adviser Mike Waltz, who organized the group thread about U.S. plans to launch airstrikes against Yemen's Houthi militants and included the magazine's editor in chief, Jeffrey Goldberg. The incident has prompted widespread concern in Washington about the administration's procedures for protecting sensitive defense information.

Trump on Tuesday signaled his support for Waltz, who had privately come under criticism from some administration officials in the aftermath of the incident. "Michael Waltz has learned a lesson, and he's a good man," Trump told NBC News.

His comments came as White House press secretary Karoline Leavitt said in a post on X that officials in the thread didn't discuss "war plans." She also said the White House Counsel's Office "has provided guidance on a number of different platforms for President Trump's top officials to communicate as safely and efficiently as possible."

The discussion over the encrypted Signal app lasted days and included specific information about weapons, targets and timing used in the attack, Goldberg reported. Leavitt also said the National Security Council is looking into how Goldberg was added to the group thread.

Goldberg and the Atlantic didn't immediately respond to requests for comment.

In an interview with MSNBC, Goldberg said the exchange was a "minute-by-minute accounting of what was about to happen" shared by Defense Secretary Pete Hegseth. "This is their plan. And he was taking their plan and sharing it with a bunch of civilian leaders."

Former government officials have said the use of Signal for conducting discussions about military plans was a serious breach of security procedures.

There were early signs Tuesday of Republicans coalescing around a defiant message. A White House rapid response account circulated a clip of Sen. Tom Cotton (R., Ark.) appearing on Fox News and commending the Trump administration for focusing on worldwide threats, while asserting that the Biden administration had failed to do so.

Hegseth, who was among 18 users in the Signal group, on Monday criticized Goldberg and said that "nobody was texting war plans and that's all I have to say about that."

Write to Tarini Parti at tarini.parti@wsj.com and Alex Leary at alex.leary@wsj.com

(END) Dow Jones Newswires

March 25, 2025 09:45 ET (13:45 GMT)

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