In the UK, the history of regulation, certainly regulation of the media, is one in which, time and again, successive governments lacked the “bottle” to enforce the powers that were available to them.  We saw this 25 years ago with Rupert Murdoch’s acquisition of the Times and the Sunday Times, when the government wriggled around its obligation to refer the purchase of either newspaper to the Monopolies and Mergers Commission, on the grounds that both papers were in imminent danger of closure.

As the passage of time has revealed, this was a somewhat exaggerated claim in the case of the Times, and wholly without foundation in respect of the Sunday Times.

As a compromise, a set of safeguards regarding “editorial independence” were incorporated into the articles of association of Times Newspapers – which were changeable only with ministerial approval.

But those safeguards all too quickly turned to dust; in fact the new proprietor later boasted that they were “never worth the paper they were written on”.

As Harold Evans writes in his book Good Times, Bad Times, “when in Murdoch’s presence, it was barely possible to believe he would break his word, however away from him, it was barely possible to believe he would keep it.”

For as Rupert Murdoch himself is reported as telling one of his biographers, Thomas Kiernan, in his book Citizen Murdoch, “you tell these bloody politicians whatever they want to hear, and once the deal is done, you don’t worry about it. They’re not going to chase after you later.”

That pretty well describes exactly what’s been going on over the last quarter of a century here in the UK.

In fairness, the rise of social media offers some genuine cause for optimism, not least because it enables people to start speaking the truth directly to power, and in ways that were unimaginable even 10 years ago.

At least in the west politicians, corporations and media moguls can no longer take for granted their power to control the public discourse – and have it go unchallenged.

So technologically and socially there can be no going back – the response to the Queen’s diamond jubilee, and the public outpouring of affection that preceded the miracle of the London Olympics, makes it clear that we’ve reached a watershed in deciding the type of nation we want to be – and wish to be seen to be.

But it’s Michael Sandel’s recent book, What Money Can’t Buy: The Moral Limits of Markets, which took me to the root of this issue.

Although his analysis is principally focused on the US; much of what he says translates directly to the Britain that’s been bequeathed to us by 25 years of obeisance to the (demonstrably false) gods of the marketplace.

Writing in the New York Times, one of my favourite columnists, Tom Friedman, summarised the book’s key insights like this:

Sandel argues that market values are crowding out civic practices. When schools are plastered with commercial advertising, they teach students to be consumers rather than citizens. When we outsource war to private military contractors, and when we have separate, shorter lines for airport security for those who can afford them, the result is that the affluent and those of modest means live increasingly separate lives; and the class-mixing institutions and public spaces that forge a sense of common experience and shared citizenship get eroded.

Throughout our society, we are losing the places and institutions that used to bring people together from different walks of life.

Unless the rich and poor encounter one another in everyday life, it’s hard to think of ourselves as engaged in a common project.

At a time when to fix our society we need to do big, hard things together, the marketisation of public life becomes one more thing pulling us apart.

“Democracy does not require perfect equality,” he concludes, “but it does require that citizens share in a common life … For this is how we learn to negotiate and abide our differences, and how we come to care for the common good.”

This is something that the most powerful and influential people on both sides of the Atlantic could be accused of having lost sight of over the last three decades.

And they’ve been encouraged to do so by a good deal of the media – whether it be the Daily Mail or Fox News.

However, encouraged by Lord Leveson’s forensic investigation and by the spirit of the London Olympics, I’d like to think that we are beginning the process of recovering a sense of common purpose in this country.

Lord Justice Leveson and his colleagues have some very difficult and incredibly important judgments to make over the coming months.

As I see it, the most important of these is which Britain to go into bat for. The manipulators or the manipulated? The self-entitled or the truly entitled?

He’ll have been told that “lessons have been learned”; that the newspaper industry will “clean up its own act”; that “any form of regulation will be an arrow aimed at the heart of democracy”; that a vigorous press cannot be held accountable for its accuracy, and that in today’s world it’s impossible to clearly differentiate between “comment” and “opinion”.

In reality none of that is true – all of it is “special pleading” intended to return matters to the old and comfortable status quo as quickly and as painlessly as possible.

Newspapers and their editors have to become as accountable as the rest of us – they are not “a special case”, and they have only themselves to blame for having lost the argument for “exceptionalism” – and with it the right to “self-regulation”.

Nothing is likely to change without the public, the politicians – and the press themselves – making it clear that they, every bit as much as us, want the optimistic and responsible Britain we caught a glimpse of at the Olympics and Paralympics.

There’s a great burden of responsibility on all of us in this.

And there is a particular burden of responsibility on David Cameron – who after all set up the inquiry – it inescapably falls to David Cameron to show leadership when Lord Justice Leveson publishes his recommendations later this year.

• This is an extract from David Puttnam’s Fulbright lecture, The Lessons of Leveson, given on Monday night at the Eccles Centre for American Studies in London.  The full lecture can be read here [doc].

This post originally appeared in the Guardian “Comment is Free” and is reproduced with permission and thanks