Modern News is a jabber, a fluster, a blizzard of bloggery. The three-way rivalry of broadcasting, print and internet promotes hyperbole and hyperventilation. We know (from the David Kelly affair) that ad-libbing reporters can bring on disaster; we are treated nightly to speculation and opinion stirred like luscious raisins into the thin gruel of fact.

We tolerate correspondents who blur news and commentary without even recognising it, ending every report with a sort of plastic moral (“But the one thing that's certain in politics - is that there are no certainties”). We watch the mission to explain turning into a licence to witter. And as broadband spreads across the world, we are aware that the most thoughtful and well-researched article posted online will instantly grow a long tail of comments, many of them mad or irrelevant. We accept that “citizen journalists” with photo-phones and unchecked facts are - in the words of Rosenberg and Feldman's prologue - now “ordained as democratising saviors, liberating society from the tyranny of competence and expertise”.

This book is mainly about American news reporting, but enough of it is recognisable to Britain and all of it is an awful warning, delivered with anecdotal richness and real passion. It begins by quoting Tony Blair's departing rant about news media as a “feral beast” and his “need” to spin at least three issues a day in the 2005 election, compared with one a day in 1997.

The authors pinpoint Blair's hypocrisy - a master spinner hoist by his own petard - but agree that he was on to something. “The much-maligned 24-hour news cycle had already shrunk to 24 minutes by the time he delivered his blistering critique”.

The feral quality of media is not something these authors ascribe to intent or bias: merely to speed. Technology has enabled reporting to accelerate to such an degree that there is, literally, no time to think. The pressure to “refresh” stories leads to twisting and gimmickry. Networks go live to events not because the events are important, but because the technology is on tap. Reporters stand pointlessly in front of buildings (the famous “guilty windows” shot) and are urgently questioned about what is going on, without having time to find out because they are on air every 20 minutes .

Sometimes the speed is used with dazzling combative ingenuity: when Hillary Clinton's “dangerous world” TV ad aired at 7am, suggesting that Obama was not the man for a world crisis, the Obama team got a counter-ad on YouTube and all the networks by noon, before most working people had seen the original one. How often, indeed, have you or I been first alerted to some vital development in the life of democracy (or Paris Hilton) by hearing the rebuttal of the denial of the story?

There is real peril in this. The BBC's famous guide for online staff is quoted - one of the few UK examples in the book - as saying stories “MUST be accurate, impartial, balanced” etc, but then adding “Get the story up as fast as you can - we encourage a sense of urgency - we want to be first”. That the two imperatives may be contradictory seems not to occur.

Rosenberg and Feldman believe that this is dangerous, to democracy and decision-making. The adage has become literally true: a lie can travel twice round the world before truth has its boots on. Who, in a private life, has time to cross-check every story? How many of us take whatever comes, unaware that it is not a finished report but a glimpse of the reporting process, stumbling through rumour and error before our very eyes in real time? How many commentators seize on a piece of nonsense and perpetuate it with an air of magisterial authority?

There are serious examples - the TWA aircraft crash in 1996 when “citizen journalists” repor-ted seeing missiles streaking towards the plane: in fact, it was downed by a fuel fault. And there are absurd ones: the singer Sheryl Crow saw on a CNN airport monitor that “Sheryl Crow has proposed that we legislate toilet paper to one square”. She didn't. It was part of an old comedy routine. The speed culture promotes misreporting, but speed is a drug: it exhilarates. The authors make the point that rapid news leads to rapid and dodgy decisions in an atmosphere of hysteria. Politicians rap out undigested initiatives; all of us suffer a “bias of convenience”, in which it is easiest to be satisfied by an incomplete or misleading answer. The internet is perfect for this: it flatters us into a sense that our hunch is right, because we Googled for confirmation not rebuttal. The web can make the world wider, but can also become a giant echo chamber.

Frank Sesno, a former CNN correspondent, offers one of the best suggestions in the book: that websites and bulletins learn the “language of live” used by Mayor Giuliani after 9/11, making it clear that information is changing. “Maybe,” he says, “you create a place called ‘story in progress' so that you can clearly convey [that] the information is incremental and developing”. Meanwhile we click, glance, misremember and misunderstand. And it hardly seems to matter, because there'll be more “news” along in a second.

No Time to Think: The Menace of Media Speed and the 24-Hour News Cycle by Howard Rosenberg and Charles S. Feldman
Continuum, £9.99; 226pp Buy the book here

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