Civilisations are remembered by the state of technology at the time. We recall the Stone Age, the Iron Age and, more recently, the ages of agriculture, industry and space.

Now, we have entered the Information Age, with the computer revolution transforming the means by which we can communicate with each other. Two recent examples of this have been covered extensively in the press, but deserve further attention.

First, the row over the release of US diplomatic cables by WikiLeaks has shown the sensitivity of those in power to the idea that the public at large is able to read memorandums and papers that the establishment prepared for its own purposes.

Similarly in Egypt at the start of the year, the masses could gather in Tahrir Square in Cairo because texting, Facebook and Twitter freed them from dependence on the official sources of information, such as state-controlled television and newspapers.

WikiLeaks and the Arab world revolts remind us of the power of free-flowing information and its role in the development of society from the time of Caxton through to Google. The result in Egypt, Tunisia and Libya has been to make possible popular revolutions that would never have taken place had this information not been available.

At the people's expense

Democracy itself depends on the availability of information - and the passing in 2000 of the Freedom of Information Act, which allows the public to have access to government policy thinking, has marked a very important step forward for all of us who benefit from parliamentary democracy.

In the old days, before a parliamentary system developed in Britain, the government carefully concealed everything that it was doing. Today, it tries to make available to itself everything that everyone else is doing by opening their letters, bugging their phones and watching their internet connections.

Both actions strengthen the powerful at the expense of the people and make it easier to control them. So freedom of information is of critical importance if our democratic system is to reflect authentically what the public wants to see done in its name by those it elects.

The sunlight of publicity is the best disinfectant and there could hardly have been a more precise illustration of that than when MPs' expenses claims were made public. Increasing the flow of information almost solved the problem: once politicians knew that their receipts were being scrutinised by the electorate, they were far more reluctant to claim for duck houses and moat-cleaning, even if it was technically within the rules.

It is not hard to see how the Freedom of Information Act could be extended to cover other areas of public affairs - not least in the economic sphere - by removing many of the restrictions on its operations that were introduced at the legislative stage. (There are 23 exemptions, covering everything from "commercially sensitive" data to matters relating to defence.)

If the pay of top executives in business were made known, for example, it would certainly increase the opportunities for the trade union movement to make claims on behalf of its members. I think this provision should become the centre of political campaigning.

Similarly, leaks of information about what the government is doing should be seen as an advantage in democratic terms. It is interesting to look back and remember on how many occasions this idea was bitterly contested - such as when Thomas Curson Hansard was imprisoned for publishing parliamentary debates in 1810, or the days when the "30-year rule" on releasing cabinet papers was used deliberately to blot out any public understanding of what had been done in the people's name.

If we are serious about encouraging democracy worldwide, the United Nations ought to be encouraging every country to publish more about what its government is doing.

We so often talk about knowledge being a means of empowerment, but should never underestimate the enormity of the task of making it available to everyone. Indeed, when I think of all the constitutional changes we propose, this would be the greatest in its practical effect on the way democracy works and what it can offer the people of Britain and the world.

A priority for Labour

With this in mind, the Labour Party, when drawing up its manifesto for the next general election, should restate its commitment to extend freedom of information along these lines and make legislating to do so a top priority of any government that it forms.

All future Labour governments should commit themselves to abandoning the practice of hacking into the private correspondence of British citizens under such illiberal legislation as the Regulation of Investigatory Powers Act 2000.

For all these reasons, we shall be able to see more clearly in retrospect why the WikiLeaks debate is so important, and why it was that new sources of information made the Arab revolutions possible.

Making these steps forward may sound easy, but the reaction of the American and British governments to the work of Julian Assange, the WikiLeaks founder, whom they speak of as if he were engaged in espionage, will need to change. In order for that to happen, we must launch a huge public campaign.

Tony Benn was MP for Bristol South-East (1950-60, 1963-83) and then for Chesterfield (1984-2001) and was also a long-serving Labour minister