Making threats to use your power as commander-in-chief against the free speech of a private company is not "trolling" or "negotiation", it's creating a chilling effect on speech whether he goes through with it or not.
I doubt he would shut Twitter down (if only because he needs it more than it needs him), but I don't doubt for a second that he would use the executive branch to retaliate against them.
I doubt he would shut Twitter down (if only because he needs it more than it needs him), but I don't doubt for a second that he would use the executive branch to retaliate against them.
https://en.wikipedia.org/wiki/Chilling_effect