On a gin-clear December day, I’m sitting under the plexiglass bubble of a radically new kind of aircraft. It’s a little past noon at the Byron Airport in northern California; in the distance, a jagged line of wind turbines atop ...

Nearly four hours into Tesla’s marathon Investor Day, someone in the audience tried again to bring Elon Musk, the Tesla (and Twitter and SpaceX) CEO back to the present day. From a stage at the Gigafactory in Austin, Texas, Musk ...