Mr. Trump would still find ways to reach his followers without Facebook and Twitter, of course. There would still be Fox News, Newsmax, OANN and legions of pro-Trump partisans willing to repost his messages. Newspapers and cable news stations, which have long treated anything a president said as inherently newsworthy, might not be able to resist giving Mr. Trump airtime and attention even when he is a private citizen. And he has expressed interest in starting his own digital media empire, where he could set his own rules.The Presidential TransitionUpdated Jan. 8, 2021, 12:48 a.m. ETThe most obvious short-term move for …