The article's author received a Signal message from a user claiming to be Michael Waltz, the national security adviser, inviting them to a group chat about a pending military action against the Houthis in Yemen. The author was included in a conversation with high-ranking US officials, including the vice president and secretaries of defense and state, discussing the operation's details. The conversation appeared to be real, and the author witnessed the officials discussing and coordinating the military strike, which was later carried out. The author notes that this is a highly unusual and potentially illegal use of a non-governmental messaging app for sensitive national security discussions.