With one final snatch of homely Texan wisdom, a cheerful bon mot for the masses, and, one can safely assume, a tear or two glistening from a wrinkled cheek, Dan Rather will say goodnight to the American people for the last time.

As the studio lights go down at CBS headquarters in Manhattan, Rather, the presenter (anchor, as the Americans prefer it) of the CBS Evening News, will end his 24-year reign as North America’s most prominent journalist.

For a generation, Rather has been not only one of the most familiar but also one of the most controversial figures in American public life. He would like to be remembered as Americans’ window on history. Whether reporting on the assassination attempt on the Pope, the collapse of the Berlin Wall or the September 11 terrorist attacks, Rather has played the role of homespun purveyor of the news that shapes the world.

However, he is likely to be remembered by half the nation as a despised icon of the left-wing elites that dominate the US media. That critique was underscored in September last year, two months before the US presidential election, when Rather presented a news report purporting to have uncovered damaging information about President Bush’s Vietnam-era service in the National Guard. It quickly became clear that the item was based on forged documents. Several of the producers involved were subsequently removed but Rather, strikingly, survived.

Yet much more than just a famous and contentious career will end with the putting out to grass of this old warhorse of American television news. Rather’s departure will mark nothing less than the final collapse of the old order of American media.

When Rather took over from Walter Cronkite, the face of US television news since the assassination of President Kennedy in 1963, he could reasonably claim membership of a small group that was the most important source of information about world events for most Americans. In those days, the men who fronted the evening bulletins that dominated the news business were not just mere readers, but editors, reporters and writers, an intrinsic part of the story itself.

Rather, and his counterparts at NBC and ABC, Tom Brokaw and Peter Jennings, who were also both appointed in the early 1980s, occupied a position something like that of the parish priest in the medieval village. He was the interpreter of events, the bringer of important news, the guider of the uninformed through turbulent times. If an American had actually brought his baby to them to be baptised, nobody would have been at all surprised; in Rather’s case he would probably have performed it.

Their status was unchallenged. CNN had just begun to beam news to a few million homes but no one thought it would survive long. There were no other new channels, no satellite TV and no internet. Newspapers were big but generally they were assumed to be in terminal decline.

Their prominence ensured them an almost mythical place in the cultural landscape, captured by such performances as Peter Finch in the film Network or Jack Nicholson as a ponderous Rather-like figure in Albert Brooks’s comedy Broadcast News. And yet it was in the Rather era that these towering landmarks of the American culture began to crumble.

CNN did not fail but spawned a whole new genre of American popular journalism.

In the 1990s Fox News (owned by News Corp, the parent company of The Times) offered a feisty alternative more in tune with Americans’ attitudes than the fusty and heavily left-wing slanted traditional networks. In recent years the internet has offered a staggering array of alternative sources of news, information and comment.

At the same time the credibility of the old network news has been undermined by scandals such as the CBS National Guard debacle last autumn.

The three network news bulletins now attract a fraction of the audiences they commanded when Rather started. These audiences are heavily dominated by the over-60s crowd (a fact attested to by the preponderance of Viagra and haemorrhoid unguent advertisements in their commercial breaks).

Last December Brokaw hung up his microphone; Rather will be gone next week; Jennings will not be far behind.

But who will be watching?

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