By Geoff Dyer, FT China bureau chief

Now that the Obama circus has left town, the biggest sigh of relief comes from the group of people often labelled as China’s “dissidents”: human rights lawyers, serial petitioners and democracy advocates. Even though the US president went out of his way to be diplomatic about human rights issues and did not have any extra-curricular meetings with independent intellectuals, Beijing still detained dozens of people and put others under house arrest