Government Communications Headquarters, or GCHQ, gathers secret intelligence electronically rather than through spies: 'sigint' as opposed to 'humint'. (There is also 'comint', 'elint', 'comsec', 'sinews' and 'sigmod'.) It was the last of Britain's three (that we know of) national secret services to be founded, and has the lowest public profile. (How many spy novels can you think of that feature 'sigint', aside from Robert Harris's Enigma?) Yet today it is probably the most important, and certainly the most expensive. It is housed in Cheltenham in 'the largest building ever initiated by the British government'. The building is shaped like a doughnut, which is the nickname given to it by its occupants; but it's also reminiscent of Jeremy Bentham's all-seeing 'panopticon'. That seems apt: it allows the government to read and hear almost every message that passes between us. In his new history of GCHQ Richard Aldrich claims that this surveillance capability constitutes potentially 'the most insidious threat to personal liberty' we face today.

LRB 18 November 2010 | PDF Download