Why did the majority of the British press ignore a story regarded as hugely important by newspapers in the United States and Europe and, for the matter, the rest of the world?

On Monday, Edward Snowden - the National Security Agency whistleblower regarded as the most wanted man in the world - did an online question-and-answer session arranged through The Guardian.

The American media were across it: the Washington Post of course (see commentary here), and the New York Times here, and the Los Angeles Times here plus the Wall Street Journal here. And most of the main metro papers across the US weighed in too.

Well, you might say, it's a big story in the USA, what with Snowden being an American who leaked American secrets.

But it was taken to be a big story across Europe too, in Le Monde and in Germany's Die Zeit and in Sweden's Expressen. And outside Europe too - here in the Times of India, and here in South Africa's Star. And plenty more.

This was only the mainstream media. The Q&A was widely discussed and dissected across the net. See Salon.com and Buzzfeed and Gigaom, plus scores more. Many thousands of tweets were devoted to it too.

Yet, with the exception of The Independent (here), no UK national paper thought it worthy of coverage.

Why? Are British newspapers' news values different from those elsewhere? Does the story itself run counter to their political agendas? Is it due to hostility towards The Guardian?

Is it a collective belief among a largely right-of-centre press that The Guardian is beyond the pale? This view emerged in a Daily Mail piece by Stephen Glover in which he spoke of the paper being so "driven by its own obsessions" as to "carelessly reveal the important secrets of the British government."

The Mail holds aloft the banner of press freedom when citing the public's right to know about Hugh Grant's private life, but it appears to find it unacceptable for a paper to inform the people that their privacy has been compromised by their own government.

Even Snowden's revelations in The Guardian that British intelligence had spied on delegates at two G20 summits passed under most editors' radars, though The Times did cover the story. Most papers, however, turned a blind eye.

As I say, I'm genuinely uncertain why newspapers that make so much of their independence from the state have failed so badly in this instance. Just why did they turn a deaf ear?