US allies have quickly had to adjust to the disruptive and often antagonistic policies of the second Trump administration. But the stunning disclosure that top US officials discussed sensitive US military operations in Yemen on a Signal message group that mistakenly included a journalist reveals something else: the sheer amateurism of the Trump White House. The breach will raise disquiet across the US security and military apparatus about the risks of such behaviour to personnel. Allies could question what intelligence they are prepared to share with Washington in future.

Government by WhatsApp has become common, as inquiries into Covid pandemic handling in the UK and elsewhere have found. But confidential exchanges between government and security officials normally take place in the White House situation room or via highly secure lines, not Signal. Though Signal is considered more secure than WhatsApp, there were clear potential vulnerabilities, notably if the conversation took place on officials’ phones; hackers and hostile security services have targeted such devices in the past.

Communications security is paramount to protect both government secrets and military and security staff. In a pre-scheduled Senate intelligence committee hearing on Tuesday, Tulsi Gabbard, director of national intelligence, and CIA director John Ratcliffe both denied that classified material had been shared in the chat. Yet Jeffrey Goldberg of The Atlantic, who was invited to join in error, says the conversation discussed “operational details of forthcoming strikes on Iran-backed Houthi rebels”, including targets and weapons. He adds that a message apparently from Ratcliffe contained “information that might be interpreted as related to” current intelligence operations. Steve Witkoff, the president’s special envoy for Russia, was in Moscow when he was added to the chat, although it is unclear if his phone was with him.