IS Edward Snowden a hero of our time?

With some reluctance, because Mr Snowden is obviously guilty of at least a breach of trust, I've concluded that he is indeed a hero, if an unlikely one.

This 29-year-old IT expert is currently languishing in a kind of self-imposed imprisonment in Hong Kong, part of the People's Republic of China. He is a US citizen who was so concerned that his own government was destroying privacy and basic liberty that he has, by implication, asked us in the West to stop trusting our governments. He certainly does not trust his, that of the ever-more draconian President Obama. He has identified himself as the source who leaked the news that US agencies gathered millions of phone records and monitored internet data. He believes that the American state's gathering of electronic intelligence is, under the current administration, out of control – and may well lead to a complete loss of individual freedom.

Mr Snowden is obviously highly intelligent, brave and modest. Indeed he does not see himself as a hero. He simply asserts that he does not want to live in a world where there is no privacy.

And yet I'd be prepared – and I suspect that most people I know would be equally prepared – to give up at least some privacy if that would guarantee our security and the security of our friends, neighbours and loved ones.

There is a vague, assumed contract, which runs like this: We live in a democracy. We have to trust our democratic elected government, and its allies, to act on our behalf. We know that they are practising ever most sophisticated and complex surveillance and that they are at times probably accepting intelligence information from other supposedly friendly powers. This, many of us would aver, is surely a price worth paying for our liberty.

But Mr Snowden has now spectacularly turned that on its head by suggesting that the real threat to our liberty is coming from our own governments, and their excessive enthusiasm for surveillance in the name of security. He is clear that he is rejecting the conduct of his own US Government. He foresees a time of tyranny. The direct implication is that instead of being concerned only about hostile powers and terrorist organisations, we should also be directly concerned about what our own governments are doing in the name of protecting of us.

At the heart of this is the notion of privacy. This is almost impossible to define. As far back as 1967, when the complex technology which Mr Snowden knows and understands was in its unsophisticated infancy, and the President of the US was one Lyndon B Johnson, the US Office of Science and Technology stated: "The right to privacy is the right of the individual to decide for himself how much he will share with others his thoughts, his feelings, and the facts of his personal life".

That is pretty imprecise, but even so it is now clear that even such vague privacy is no longer guaranteed. In some ways this should not shock us; after all, the right to privacy is not specifically guaranteed in our own UK constitution, such as it is, and it is recognised legally only indirectly, in such matters as libel, breach of trust and so on.

To put it another way, if one individual is spying on another in the UK that individual is not necessarily committing a crime. If your own government is spying on you, it is not necessarily committing a crime either. William Hague, the Foreign Secretary, is probably correct and sincere when he says that Britain does not act outside the law. On the other hand, there is provision for both judicial and ministerial scrutiny: are these effective?

Mr Snowden, meanwhile, is not concerned with mere legal niceties. He is almost apocalyptic in his fear of an impending world where governments know everything and anything they want about us. He reckons this will inevitably lead to a loss of individual freedom and individual creativity. In effect, the state would know, and thus control, everything.

Mr Snowden obviously speaks with insight and authority; he understands the complexities of the surveillance industry. His warnings will have to be taken very seriously as the repercussions of his whistleblowing unravel over the next few days. .

And yet he was not even a direct employee of the US government. He worked for a contractor, and he was quite far down the line. How many more thousands of people know far more than he does? Further, the fact that Mr Snowden worked for one of many contractors operating in this murky area indicates just how huge the security industry has become. The task is to guard the guardians. When there are vast cohorts of guardians this becomes difficult and almost impossible.

I sometimes think, when subjected to the pervasive and intrusive "security" that is now a routine part of air travel, that the terrorists have already won. Maybe they've already won in an even bigger way: the threat that they pose allows all our western democratic governments to assume, no doubt with decent intentions, ever more right to intrude ever more deeply into all our thoughts and actions.

Mr Snowden is in effect warning us of a world in which there are no secrets any more. You could argue that in theory that is no bad thing, but I sympathise with him. The right to privacy is paramount, and if governments breach it in a systematic, routine and relentless manner, they can hardly pretend to be the defenders of freedom. Mr Snowden's action is a direct challenge to the US Government and to President Obama personally; but it is obviously also a challenge to our Government.

Nobody is denying that the US government can and does share information with our Government from time to time. So what is our UK Government to do? Reject information passed on to it? Or delay until it is wholly satisfied as to exactly how the information was gathered? This eventually comes down to trust. Mr Hague seeks to assure us by saying that we can never be aware of all the things that are being done to stop terrorists blowing us up. That is true, but it hardly amounts to a licence to do absolutely anything in the name of security.

Mr Snowden's intervention is so devastating because he makes us ask the simple questions: Who can we trust? Can we trust our governments?

So he has already achieved a great deal in a very short time. He has started an intense, wide-ranging debate on the limits of state power. He has asserted the right of the individual against a vast and unbelievably expensive security industry.

These days, our security and our civil liberties are barely compatible. To ensure that we are secure but also free and entitled to our privacy is almost impossible. But it is what western governments must strive to do; otherwise, the terrorists will indeed have won.

Colette Douglas Home is away.