Louisa Lim: To write my book The People’s Republic of Amnesia: Tiananmen Revisited, I spent a lot of time in fast-food restaurants. Not because I like burgers, but because dissidents often favour the crush of diners and the buzz of conversation, believing it complicates surveillance. As I sat in McDonald’s with Bao Tong – who spent seven years in jail as the highest government official to be sentenced post-Tiananmen – he could point out which plainclothes policemen were shadowing him. Read in full.