When an unwanted house guest finally departs, the relief is palpable. So it is with the news that Julian Assange has left Britain. On June 24th the founder of WikiLeaks, a website that publishes classified and sensitive information, walked out of Belmarsh, a high-security prison in south-east London where he has spent the past five years, and hopped on a plane to Thailand. From there he is headed to the Northern Mariana Islands, an American territory in the Pacific, where he is expected to plead guilty to one charge of violating America’s espionage laws. That will fulfil his side of a reported deal with the American government, which in return will allow him to go home to Australia.