The app facilitated communications in a building where cell service is poor and personal phones are not allowed in some areas.

Pete Hegseth just can’t stop himself from using Signal. The defense secretary installed the encrypted-but-unclassified messaging app on a desktop computer in his Pentagon office to work around restrictions that prevent him from using personal devices to communicate with people outside headquarters.

President Trump and Vice-President Vance are standing by Hegseth despite the swirling controversy over his handling of the Defense Department.