So how much has changed in the US in the 30 years since the foundation of London University's Institute of United States Studies, celebrated this week with a party at the US ambassador's Regent's Park residence? The ambassador, Admiral William Crowe, announced: "We have a legal system in which a man is presumed innocent until he is appointed to a job by the president." He redoubled the ensuing laughter by adding: "And that would be a lot funnier if it weren't true."