When it was officially announced in late August that statistician Liu Jun had left Harvard University and joined Tsinghua University in Beijing, speculation ran rampant. Was it political tension? Research funding cuts? A backlash against Chinese academics in the US? For Liu, the answer is simple – and deeply personal. It “has nothing to do with Trump”, he said in an email to the South China Morning Post, explaining that his decision was not out of political protest or professional...