SEOUL, South Korea — Among countless mourners at a public square in North Korea, the kneeling middle-aged man in an off-white windbreaker stands out. The state broadcaster’s camera zooms in as he wails, rocking back and forth with clenched fists, his grief punctuated by the white puffs of his breath visible in the cold of the capital, Pyongyang.

The camera lingers a few seconds too long on this perfect mourner. A couple of rows away, two teenage boys stand motionless, seemingly uncertain about how to behave. They look toward the man — perhaps even at the camera beyond him — then briefly away, before also dropping to their knees to weep.