Donald Trump was apparently mad at Elon Musk for planning to attend a secret briefing on China at the Pentagon last month.

LONDON — A magazine journalist's account of being added to a group chat ... Signal messaging app hours before strikes on Iran-backed Houthi-rebels in Yemen order by U.S. President Donald Trump.

An image of the Signal app is shown on a mobile phone in San Francisco, March 18. LONDON — A magazine journalist's account of being added to a group chat of U.S. national security officials ...