How many police officers does it take to neutralise a single unarmed protester? According to a video purported to be from China, it takes at least 10 highly disciplined members of law enforcement, as well as some bespoke blue banners. In footage that emerged on Thursday, black-clad officers are shown practising a drill to surround a single person holding up a white piece of paper – an item that became the symbol of the anti-lockdown protests that rocked several major Chinese cities at the end of last year, and the demonstrations against the security laws imposed on Hong Kong in...