This observation by the journalist David Cay Johnston in the recent channel 4 documentary Trump: An American Dream stood out to me:
Donald understands that most reporters accurately quote what they’re told but they really don’t know what they’re writing about. Once his story is out there then anything else is just a counter story.
It’s far from a new analysis but I’ve rarely heard this stated so succinctly. This is a tactic Trump has been using for decades, though it’s been super-charged in recent years by the multiplication of communication channels creating more possibilities for the original claim to spread and fewer possibilities for counter stories to authoritatively take hold.