Air travel is different from other sectors in degree but not in kind. In a few generations, it has gone from a Tomorrowland-style marvel, accompanied by luxury service, to a series of petty frustrations and humiliations. Like rail travel, which was also once steeped in a certain glamour, it has suffered the effects of a lack of competition and declining investment in public infrastructure. Airlines needlessly demean customers, who are gouged for fees to goose the margins of tottering industry monoliths like United. The process begins when you first shop for your ticket. It is not enough to book passage on a plane. Instead, you are besieged with offers — to book bags, to upgrade, to get more leg room, to gain access to a preflight lounge, to board earlier, to acquire insurance — each of which costs an additional fee. The inducements continue all the way through check-in at the airport and practically until you land at your destination. Any flier who has tried to nap after takeoff knows the exasperation of trying to block out a credit-card ad delivered by airplane public-address system.