Trevor Paglen describes himself as a landscape artist, but he is no John Constable. The landscapes Paglen frames extend to the bottom of the ocean and beyond the blurred edges of the Earth’s atmosphere. For the last two decades, the artist, a cheerful and fervent man of 43, has been on a mission to photograph the unseen political geography of our times. His art tries to capture places that are not on any map – the secret air bases and offshore prisons from which the war on terror has been fought – as well as the networks of data collection and surveillance that now shape our democracies, the cables, spy satellites and artificial intelligences of the digital world.