Horace Ov?ackled that very problem of identity head-on in Pressure (1975). The point about The Harder They Come is that it earned its popular-cultural resonance through its celebration of reggae, Jamaica's indigenous music and prime cultural export. The film's star was Jimmy Cliff, a man possibly cooler than Clint Eastwood (he's definitely a better singer). Because, over the last three decades, from Ov? Pressure to Amma Asante's A Way of Life, black British cinema has transformed the way it looks, the way it sounds and and the way it feels. But where did it come from? A good starting point is Perry Henzell's iconic 1972 Jamaican movie The Harder They Come. This is the image on the poster of Pressure, a 1975 film by the Trinidadian director Horace Ov? the film that is widely acknowledged to constitute the birth of black British cinema. Arguably, this fast-moving "rocksteady" cowboy caper provided the first meaningful cinema-going experience for Caribbean immigrants and their UK-born offspring, because it gave them a chance to see something of their culture on screen.

Britons of African descent may point to the great Senegalese film-maker Sembene Ousmane as their talisman but his oeuvre has always been strictly art-house. The season provides an opportunity to reflect on "Black British Cinema" - to consider what such a thing might be, where it came from, and what it has to say about Britain now. This and other equally emblematic works, such as Menelik Shabazz'sBurning an Illusion, Isaac Julien's Looking for Langston and Saul Dibb's recent hit Bullet Boy, are all being shown at the National Film Theatre's ongoing Black World season. There are plenty of kids in America who get their news from Jon Stewart because they no longer bother to separate the facts from the mockery.In some ways, this is valuable and democratic. The big three have not really been the big three for a while - they were a forlorn gesture towards nostalgia They, and CNN, were the channels to go to in a crisis. But more generally, viewers knew that there was a mess of news on television, some of it very loaded with spin, some of it flagrantly unreliable or petty in its focus; and some of it satirical. Anyone has felt that community and compassion at our worst (and best) moments: not just 9/11, but the death of John Kennedy or Princess Diana.

We know the terror there might be if there was ever a great light in the night sky and then nothing on television.This idea behind the necessity of mass media had a great deal to do with the attitudes implicit in television: the relative paternalism of British broadcasting is just one example of television and radio in conveying confidence But technology has already ripped away that fa?e. It was that heavily populated societies (the nations of the 20th century), feared chaos or disorder.Mass media served this purpose: they said, be calm, we are all here together, we are being spoken to - the plane has a pilot. There will be successors, but the three network news shows are now lucky to have 25 million viewers on any night. Once upon a time, when the three networks ran television, and the anchors were Walter Cronkite at CBS, Chet Huntley and David Brinkley at NBC, Harry Reaskner and Frank Reynolds at ABC, each network might have had 25 million.If this seem a little remote from Film Studies, let me remind you that one area of concern for this column has always been whatever we do with screens and the personalities that depend on them. In Britain as much as the US, in the early days of radio, movie or television, there was a great deal of theorising on the nature of a mass medium.