Much progress has been made in attitudes towards sexual equality and gender identity – but in many places a dramatic backlash by conservative forces has followed. By Mark Gevisser

On a visit to Senegal in 2013, Barack Obama held a press conference with the Senegalese president Macky Sall. “Mr President,” asked an American journalist, “did you press President Sall to make sure that homosexuality is decriminalised in Senegal? And, President Sall,” the journalist continued, “as this country’s new president, sir, will you work to decriminalise homosexuality?”

The question was inevitable: the previous day, while they were flying over the Atlantic, Obama and his staff had erupted into cheers when they heard that the US supreme court had overturned the Defense of Marriage Act, paving the way for same-sex marriage across the country. The president had issued a statement from Air Force One: “The laws of our land are catching up to the fundamental truth that millions of Americans hold in our hearts: when all Americans are treated as equal, no matter who they are or whom they love, we are all more free.”