Now we see it. The West, or shall we call it, “the international community”, is paralysed in the face of one of the most barbaric and systematic ethnic cleanings of the 21^st Century. We are talking Syria, although it has uncanny similarities with Sri Lanka.

Once upon a time we were talking Sierra Leone – a very successful small-scale intervention in which citizens were saved and democracy restored – but that was in the last century.

Once we talked Kosovo – Western intervention without UN sanction.  Afghanistan followed and Iraq too, dogged by a desperate Anglo-American-led bid to get the United Nations to legitimise it. And finally we hit Libya, so hard we rained enough bombs to help bring about regime change that was not sanctioned at the United Nations. And then, when it came to Syria, we hit the brick wall of a Sino-Russian veto against just one more intervention that had already been cast in “regime change” terms.

Read more: Exclusive – Syrian doctors ‘torturing’ patients

Add to this the tinderbox that is the Middle East and the International Community dare not light even one match. In any case as President Obama reminded us last night,  the US wouldn’t rule out using force against Iran to stop it constructing a nuclear bomb.

Saudi Arabia says it wants to arm the Syrian rebels. Some think they already have. Our own Foreign Office says there is not much of a coherent unified opposition to “support”. For the first time that I can remember, Syria’s hard line ruling Baath Party is being described as Shia. Technically they are, but deeply secular. Yet the very fact that these Shia roots exist, and that Shia Iran is now Syria’s closest ally, scares the daylights out of the Saudis.

So we now have a picture of the “West” being against Iran, and Syria; whilst supporting Israel and the Saudis. You have the Israelis wanting to bomb Iran to stop any further nuclear development, and the US seeking the same goal, if not yet the same means. You have Russia and China supporting the Syrian regime but becoming increasingly sensitive about what that is doing to their prestige.

Meanwhile no one is talking to anyone, beyond the people they always talk to. Israel’s Prime Minister Netanyahu is in Washington again today talking to Mr Obama.

We are caught in what is inescapably a Sunni Shia war into which the West is stumbling. But that stumbling is a desperate shoe shuffle designed never to have to fire a shot in anger.

Read more: The Horror of Homs

So in the second decade of the 21^st century we have devised the mechanisms for transmitting crude evidence of atrocity. Thanks to courage and the mobile phone, the world’s citizenry is better informed about the bloodletting in Syria than during any massacre at any time in history.

This is Sri Lanka all over again, except that this time we don’t have to wait until the massacres are over, we can see them as they happen. We citizens know as much as those in power. That’s new. It is a very inconvenient truth, because what it describes is an international system so abused by its members that it can no longer function in a most desperate hour of need. So what’s to be done?

You can follow Jon Snow on Twitter @jonsnowC4

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.