SF author Charles Stross has a lovely alternate-history thought experiment which demonstrates quite neatly how British surveillance is indistinguishable in practice from totalitarianism. And if you're in any doubt, you've only got to read today's news:
The Government is facing calls to reveal the truth about a spying operation on one of Britain’s most respected human rights activists.
Previously secret documents show the late Martin Ennals was put under years of surveillance by Special Branch. He was a key figure at Amnesty International and the National Council for Civil Liberties – now known as Liberty – and a leading campaigner against apartheid.
Details of his marriage, family and holiday destinations were recorded. His luggage was also regularly searched as he made trips to and from Britain. But the files, released by the Metropolitan Police under the Freedom of Information Act, have been heavily redacted.
Any suggestion that Ennals was any sort of "security threat" is laughable. He was spied on because he challenged government policy around human rights and support for apartheid. People should not be targeted in this way in a democracy - and the fact that he was, and people like him today still are, suggests that the UK is not and never was a democratic state.
Spies and spying are simply incompatible with democracy. If we want to control our government, we have to get rid of them. It's that simple.