Kate Raworth at the Bali conference

What caused the US to join the global consensus to start tackling climate change in Bali? Thanks to the UN webcast of the conference, we can all see how developing countries shamed them into rewriting their position. It was an amazing display of last-minute international pressure, brought to life with pantomime-style booing, hissing and cheering - but the unfolding story was no joke.

You can watch highlights of the webcast on the UN website. Click on Conference of the Parties, 8.30am-3.30pm, Part Three, English Version. The timing of the highlights are given below, so you can view them in the webcast.

The conference was supposed to have been wrapped up on Friday 14 December but, after two weeks of negotiations, there was still no consensus on the text. So the negotiators carried on late into the night, and met one more time on Saturday morning. The UN had only booked the conference centre until that evening: could they leave with a deal in hand?

To everyone's surprise, Ban Ki Moon, Secretary General of the United Nations, had flown back into Bali, and he opened the morning session (select 12 minutes into the webcast) with a stern speech to the packed conference room, hoping to prevent last-minute breakdown: "I come before you very reluctantly...I am disappointed at the lack of progress...the hour is late - it is time to decide."

What exactly did they still have to decide? The negotiations were stuck on the crucial point of what kinds of obligations rich and poor countries should take on to cut their carbon emissions.

In the text that they were trying to finalise, Section B1 stated that rich countries should take on 'commitments or actions' to cut their emissions. Why the option? Commitments are binding targets for cuts (like those under the Kyoto agreement) but the US insisted on including 'actions' as an alternative so they could just take on voluntary cuts. Other countries, rich and poor, knew that including this far weaker option was the only way to keep the US at the table, but they also knew it fell far short of what the US should be doing, given its role as the biggest historic emitter in the world.

Section B2 stated that developing countries should take 'measurable, reportable, and verifiable' action to cut their emissions. That is a far stronger obligation than they have ever taken on before. During the negotiations, developing countries had said that they would only agree to this so long as rich countries supported them with technology transfer and finance to do it - and that this support must also be measurable, reportable and verifiable (because too often in the past such promises of support had come to nothing).

So on this final morning, the question was whether all countries would agree that this was a fair balance of obligations for rich and poor countries to take on. The room was packed with negotiators, but also with NGOs crowded around the edges of the room, reminding all delegations that the world was watching. The tension in the room was palpable.

Following Ban Ki Moon's opening plea for progress, many developing countries and the European Union spoke out to say they endorsed this balance of obligations, and so momentum for achieving consensus began building in the room.

But then the US intervened (select 40 mins). Paula Dobriansky, the lead negotiator, said that developing countries had not taken on the level of 'commitments' that the US had been expecting of them and so, "We are not prepared to accept this formulation at this time". There was spontaneous booing and hissing across the room - and the Americans were visibly taken aback by such international disapproval.

South Africa then put into words what the vast majority of countries were feeling (at 45 minutes): "The reference by the US to developing countries not accepting their full responsibilities is most unwelcome and without any basis...the commitments by developing countries in B2 goes further than what is expected in the UN convention. Developing countries are saying - voluntarily - that we are willing to commit ourselves to measurable, reportable and verifiable mitigation action. It has never happened before. A year ago it was totally unthinkable...Admittedly, we would have liked to see a much stronger commitment from the United States in B1...So we would like to request the US to reconsider their statement".

The room broke into applause and cheering. The pantomime was in full swing.

Brazil came in forcefully too (at 49 minutes), reiterating that developing countries were taking on 'measurable, reportable, verifiable' actions and that those countries with the responsibility to lead because of their historical responsibility (hello America) should do the same. Again, spontaneous cheering across the room.

Tuvalu spoke passionately on behalf of all small island developing states: "We have all attended this meeting with great expectations...this is a crucial issue for small island developing states...I would strongly ask all Parties in this room to accept this text".

By this point, every intervention calling for the US to move was getting passionate applause.

Uganda came in (at 1 hour) and said to the US, with great eloquence, "We would like to beg them that they do accept this position". In that moment, Uganda turned on its head the old idea of Africa begging the US: now, not begging for help from a place of poverty, but begging for US reason, from a place of moral superiority. The room could feel the moral force of rich and poor countries subtly shifting.

Tanzania (at 1 hour 3 minutes) - wedged in their seats between the US and the UK - made an impassioned plea for understanding on the part of the US, "who have the power to block progress, and in their hands lies the power to wreck the progress that has been made thus far...Let's leave Bali having made a footprint, for future generations to say proudly that we were here."

Then came Papua New Guinea (at 1 hour 5 minutes), making one of the shortest but most powerful speeches of the whole conference. In full: "We all came with high expectations. The world is watching us. We left a seat for every country. We asked for leadership. And there is an old saying: if you are not willing to lead, then get out of the way. And I would ask the US: we ask for your leadership, we seek your leadership. But, if for some reason you are not willing to lead, leave it to the rest of us - please, get out of the way."

The room went wild with cheering. The US negotiators started scribbling notes, swopping papers, avidly discussing. They suddenly asked for the floor again (at 1 hour 7 minutes). The room went still. What would they say now?

Paula Dobriansky: "We have listened very closely to many of our colleagues here during these two weeks...I've especially listened to what has been said in this hall today...We are heartened by the firm commitments that have in fact been expressed by the developing countries.... We want to be part of a Road Map, and also to do our part....so with that, Mr Chairman, let me say to you that we will go forward and join consensus in this today."

And then there was massive cheering. But it was not for the US. It was out of huge relief that developing countries had succeeded in pushing the US to shift ground, and that there would at last be a global consensus to start moving forward on fair terms. Bali could have delivered so much more, but at least it delivered this much.

What happened after the pantomime was over? The very next day the White House said the US had 'serious concerns' over the consensus, and that developing countries - especially China and India - would have to do far more if there was to be a fully fledged global deal by 2009.

So the show must go on for at least two years. And as with any pantomime, audience participation will be essential all the way. That's why all of us, in every country, must keep on watching and booing and cheering our politicians. Only then will we have a chance of getting somewhere close to a happy ending.