Top Trump administration officials used the messaging app Signal to share war plans and accidentally included The Atlantic magazine’s Editor-in-Chief Jeffrey Goldberg in the encrypted group chat. Goldberg published a first-hand account on Monday detailing a discussion that happened over the app, hours before strikes on Iran-backed Houthi rebels in Yemen ordered by President Donald Trump. Signal is an app that can be used for direct messaging, group chats, and phone and video calls. As the app uses end-to-end encryption for its messaging and calling services, a third party cannot view conversation content or listen in on calls. “In other...