Much as I like much of what the Trump administration has accomplished in its first three years, the president's use of Twitter as a prime communications source has given him much grief--and now his unfortunate word choice in his Tweet about the National Guard and rioters in Minnesota adds more fuel to the fire. If I was his PR person I'd advise him to employ a 10-minute rule before hitting the "send" symbol: wait 10 minutes, then thoughtfully reread his messages before posting them and correct as necessary. . . .