Until, of course, in 2013 the Silk Road was shut down by FBI agents and Mr Ulbricht, then 29 years old, was arrested in the science-fiction section of a San Francisco public library. In 2015, after a four-week trial,

Law enforcement said Ulbricht created the “most sophisticated and extensive criminal marketplace” on the internet.

Donald Trump pardoned the creator of the world’s first dark-web drug market, who is now a libertarian cause célèbre in some parts of the crypto community.