On Shanghai's Bund, it's a relief to see the waterfront thronged with people. Last time I stood here – back in February 2020, in the first days of the Covid-19 pandemic – I was entirely alone.

Authorities said at least 36 people died and another 47 people were injured in a New Year’s Eve stampede on Shanghai’s Bund waterfront. The victims were largely young and female. Footage from ...