On Sept. 11, 2021, to mark the 20th anniversary of the attack on our nation, President Joe Biden attended a ceremony in New York City with former Presidents Barack Obama and Bill Clinton. Biden did not speak, but he was the cause of an inadvertently illustrative image. A photographer caught him with his mask down, apparently shouting to get somebody’s attention, while the fellow attendees stood by somberly. Standing next to him, Obama — never one with a good poker face — seems to give him a sideways glance, as if to say, “C’mon, man. You’re the president. Act like it!” The scene was a perfect snapshot of a challenge Biden is thus far failing: adapting his emotive persona to his new position. Uncle Joe has spent so many years trying to be just one...