Waltz was at the center of the Signal chat controversy, in which a journalist was accidentally included in a discussion of sensitive military information.

Signalgate tarred the Floridian’s reputation, but organizational issues were cited by sources for his downfall.

President Trump removed Mike Waltz as National Security Adviser and nominated him to be the U.S. Ambassador to the United Nations. NBC News’ Vaughn Hillyard reports more details about Waltz’s potential replacements.