Heck he told Vladdie to ‘cut it out’!
There is ‘red phone’ service, which is an encrypted telephone to our own and NATO powers. However, this is not the same as the secure data link to Russia which has always been teletype, or printed words. If you are threatening war, or trying to stop one, the precision of written communications is essential. Still, I shudder at his ability to create a crises out of nothing.