For weeks, Beijing has teetered on the edge of a hard, Covid-induced lockdown. For the most part, citizens are unruffled, confident that the restrictions that have paralyzed Shanghai for six weeks are simply unthinkable in the capital. In recent days, primary and secondary school classes have been forced to move online. Restaurants and bars have been closed to in-store dining, dozens of subway stations have been shut and supermarket shelves have been stripped bare and then restocked several times.