Once or twice in a reporting lifetime, a journalist is allowed by events to participate in a project that can affect history. The film I have narrated tonight on Channel 4 – Sri Lanka’s Killing Fields – airs at 11.05 pm. It is a painful, and complex team achievement in which we have pieced together an account of what happened in the closing weeks of Sri Lanka’s civil war.

Bluntly, our evidence shows how Tamil civilians were corralled into one ever diminishing piece of land and systematically shelled and bombed by government forces. Some of the targets were medical facilities emblazoned with the internationally recognised Red Cross.

The United Nations believes at least 40,000 civilians were massacred in this process. Our evidence of how it was done comes in the form of mobile phone footage, Tamil and government film footage, and mobile phone “trophy footage” in which soldiers filmed themselves abusing and executing Tamils who had either surrendered or been captured.

War crimes were committed on both sides in what was a barbarous conflict. But the Government action that we report tonight transcends anything seen during this phase of the civil conflict.

It is a harrowing and difficult film to watch. But it represents not only the evidence required to convict, but a first ever testament in the digital age to the dawning truth that in this age it is becoming close to impossible for warring forces to cover up what they have done.

The United Nations own panel of inquiry is already satisfied that a war crime occurred on the scale and of the nature that we report tonight. Whether those responsible are brought to trial at the International Criminal Court, or at the Hague will in part depend upon the pressure from those who see this film upon their own politicians to support the ringing for charges.

Channel 4 is lifting its normal commercial access restrictions to allow the film to be freely seen by anyone anywhere in the world. Additionally, it is bound to go viral via Youtube.

This is not my normal kind of Snowblog. I end by asking you to watch this film. It could well prove a kind of a watershed, a moment when humanity, confronted with the evidence, cries ‘no more’. In our century of war – as the 21st Century is already beginning to feel – this could provide a moment when the perpetrators of war crimes meet the law courtesy of global disgust and pressure.

You will see that the film had to be, as it is, horrifically true to the facts of what happened. I hope you will spare 50 minutes tonight, it could be that it will make a difference.

@jonsnowc4

Sri Lanka’s Killing Fields will be available to watch on 4oD as soon as possible after broadcast. Channel 4 News will also be broadcasting a preview of the film during tonight’s news broadcast.

Virtually every international operative of any stature was there, in one vast room.

The ‘there’, was here, in Geneva, the UN’s other home. Ban Ki-Moon came in at 9am, spoke for 10 minutes and disappeared.

A well-honed, well-delivered speech, but no sense of occasion or presence. Behind him, however, a phalanx of heavyweight talent.

Pascal Lamy, the Director General of the World Trade Organisation – dynamic, brusque, no nonsense and the man whose mere invitation had ensured that the others all turned up, including Ban Ki-Moon.

Angel Gurria, the charismatic orator who heads up the OECD came next. Behind him Robert Zoellic the American former trade secretary now head of the World Bank, who is again extremely impressive in the flesh. Dominique Strauss-Kahn of the IMF. Helen Clark, the former New Zealand Premier who heads the UNDP. The cast went on and on.

What struck me was that these global institutions are currently in exceptional hands. But what also struck me was that the representative bodies that tag around in their wake are amazingly cumbersome. The room at the WTO sported a delegate and some sort of support from virtually every member state of the United Nations.

Hundreds and hundreds of thousands of air miles had been burnt to get them to the event. Their capacity to interact with these speakers was limited by the size of the room and the length of the day. The whole thing might have been infinitely more effective had it been done via a video-conference online.

The event? I have got this far without even mentioning it; it was a review of the Aid for Trade project – about countries in the north assisting in developing the trading capacity of countries in the south by investing infrastructure and systems that will level the trading playing field. This while the latest trade round, the ‘Doha round’, is stalled (incidentally everyone I spoke to felt the deal at Doha was there for the taking if only the Americans (and a few others) will get behind it).

The session I ‘facilitated’ followed Ban Ki Moon’s. It started with a highly structured debate.

Then the EU Development Commissioner Louis Michel, who was on my panel, turned to me and whispered: “This is boring – get them to stop reading.”

So I did, I banned all pre-prepared scripts as delegates and panellists had simply been reading from prepared statements.

Suddenly the whole thing lit up and people said what they meant.

Sounds boring I know, and in some ways it was, but it was a fascinating insight into power, powerlessness and the state of global institutions in a globalised world where globalization itself has run into such thunderstorms.

I will do another session today – likely to be far more interesting, to which I will return in my next Snowblog.