Over the past 25 years, Channel 4 has been predominantly a factual channel, with provocative and challenging current affairs at the core of its broadcasting for much of the time.
Not surprisingly, the area has generated a lot of heat – as this year's debates about radical Islamic preaching depicted by Undercover Mosque and the truth about global warming again demonstrated in spades.
But what the history I've written also shows is that in the early years, current affairs was a minefield, creating such extreme tensions between the founder, Jeremy Isaacs and his chairman, Edmund Dell, that it seemed the youthful company would be torn apart. Or that one of them would have to go.
Channel 4's then deputy chairman, Sir Richard Attenborough, once in September 1983, a year after launch, had to intervene the night before a crunch board meeting, to try to get them to compromise. He remembered an interminable private dinner from hell.
They were, he said: 'Like two tigers at the table, fierce. The confrontation was so overt. My concern at this point was to save Jeremy. It had to be. Everyone in the company knew either one or the other faced having to leave the board.'
At issue was whether Channel 4 could break the established television convention of presenting balanced, but often bland coverage of major political and social issues and broadcast opinionated programmes with bite and attitude.
Dell, to some extent backed up by the regulator, maintained that Channel 4 had a built-in anti-Tory bias and was acting as the unofficial opposition to the Thatcher government by commissioning too many programmes from one perspective only – the left wing.
Isaacs, for his part, soon agreed there needed to be more of a mixture, but he was absolutely determined to bring in fresh voices and viewpoints: That was the point of Channel 4.
There had been no new TV channel since BBC Two in 1964 and television was way behind other media in depicting a changing, diverse, multi cultural society, another of Channel 4's duties.To that end, he appointed a television novice, Liz Forgan, the women's editor of The Guardian, to run news and current affairs in a bid to inject the kind of lively thinking that newspapers specialised in.
This was like waving a red rag to a bull. Her arrival in 1981 was the formal start of six years of battles over bias until Dell stood down as chairman. Dell was also particularly exercised by programmes about third world development, which he thought were naive.
The problem was that broadcasting operated under a legal obligation to be treat politics and public issues impartially, and that pertained to Channel 4 as well. Isaacs' solution, to run a balancing discussion after a pointed current affairs programme, was not seen as a particularly practical solution later audience research showed, as viewers often missed them.
He partly resolved this by hitting on the formula, Diverse Reports, which began a lengthy run in 1984, in which well-made opinionated pieces and presenters competed for attention.
Isaacs had joined Granada Television after Oxford and national service in the late 1950s, and had been a part of the move to free up political reporting masterminded by his editor, David Plowright. He been the editor of This Week and briefly editor of Panorama before the BBC dismissed him.
He had been fired from Thames Television for letting the BBC have footage of a banned programme about the RUC's mistreatment of IRA detainees. This strengthened his determination to mould Channel 4 as a place for serious debate.
Another of his initiatives was to see if Channel 4's weekly current affairs programme could be produced by women only and if they would tackle different subjects.
Forgan handed out contracts to two groups of women. One became the esteemed Twenty Twenty independent, still run by Claudia Milne.
She pursued the best story of the week, and her scoops included an award-winning programme about the inhumane treatment of Greek mental health patients – who were hosed down like cattle – to a programme, initially banned in January 1984 on the abuses of MI5..
Channel 4 was advised it would break the law in broadcasting, so it was sent back to Milne, who duly screened it for MPs. Two weeks later, the broadcaster was told it could be shown, an important advance. (It built on this with a further innovation in 1988, televising evidence at key trials, by hiring actors to read out the words given in evidence).
The other was a collective of talented women broadcasters, called Broadside, whose first programme was about the Greenham women, protesting about cruise missiles. Forgan, in retrospect, said the case that women did things differently was largely unproved. But the early programmes did suggest that politicians tended to respond in a more human, less poised manner.
There were plenty of casualties in this era. Ken Loach made a series on union leaders, which came to the conclusion they were all betraying the rank and file: It was never shown and Central Television withdrew it. Another series, called Crucible, ostensibly about science, was cancelled. The last straw, fumed Forgan, was when a programme about theme parks turned into a diatribe against the way capitalists controlled their customers. Yet another made in 1987, called Mother Ireland, about the women who supported the Republican movement, made by the Derry video workshop was delayed until the Channel 4 Banned season five years later.
One strand almost immediately under review from week one – when it knocked off the House of Lords in a two minute rant – was The Friday Alternative, a snazzy programme screened the same night as The Tube, and aimed at younger viewers. It came off air in July 1983, after a final programme which criticised Channel 4. The programme tape in fact was delivered by mistake to the BBC and it missed its slot.
One explanation for the tensions is that, with hindsight, it now seems politics and current affairs television mattered far more when there were fewer channels and less output.
One of the most serious challenges in Channel 4's history came in 1991, when the channel broadcast The Committee – the fall out lasted a decade. This flawed film featured a single source A who alleged collusion between Protestant paramilitaries and security forces in Northern Ireland, to commit murders. The refusal to name the informant led to contempt of court proceedings and the channel was fined £75,000 by Lord Justice Woolf.
More recently, current affairs has suffered from the general desertion by viewers: Audience shares have halved and during 2001-2004 the flagship Dispatches was moved around, reduced in frequency and sent into exile at the weekend. However, it was restored to prime time in 2005 and turned into a regular weekly feature on Monday evenings. So Dispatches now looks secure while Unreported World was given a place on Friday evenings, where once The Friday Alternative briefly fizzed.
To some extent, then, current affairs has found its way again recently by focusing hard on global disorder, the clash between Islam and the West, and environmental and green issues.
The problem now is that there are not that many independent producers able to deliver such exacting programmes.
Maggie Brown is a media writer. Her book, A Licence to be Different – The Story of Channel 4, is published by the BFI. Go to www.bfi.org to order