The African nations that walked out of the climate negotiations on Monday, just hours after the Barcelona meeting started, returned late yesterday. The point of the day-long demonstration was made. Delegates of the 192 nations gathered here to make significant progress on a new climate treaty next month in Copenhagen are frustrated, terribly frustrated with the United States for not taking two momentous steps. One is defining the quantity of carbon it is ready to remove from the atmosphere. And the second is putting on the table a definite dollar amount the U.S. is prepared to invest to help developing nations make the transition to cleaner and economically greener economies.

Given the scary hazards of climate change – more killer storms, rising seas, farmland turning to dust, and time running out on reaching agreement on a global plan that leads to a solution  – there’s considerable sympathy, even in the American delegation, for the oft-expressed sentiments of annoyance that world leaders are conveying publicly in the media and privately to the U.S. delegation.

Jonathan Pershing, the deputy special envoy for climate change and the chief American negotiator in Barcelona, said as much to start the week when he explained in a news conference that the Senate deliberations on a new climate and energy bill was an impediment to the Obama administration’s ability to commit to carbon reduction limits and investments for developing nations. The administration is mindful of what happened at Kyoto in 1997 when the U.S. signed the climate treaty but never submitted it for Congressional approval.

That was just fine with President George W. Bush, who never really embraced the dangers of climate change, rejected the treaty, and seemed to delight in jabbing his thumb in the belly of the U.N. and global negotiators for eight years. Pershing said as forcefully as the conventions of nuance in the diplomatic dialect spoken at such gatherings that the administration is committed to ensuring that the climate negotiations proceed to a satisfying conclusion in Copenhagen.

Pershing said “development of a domestic number is under way and we are actively working with the Congress.” He cautioned against deciding “how blame is apportioned. That is not a constructive thing. We think we can get there. The constructive thing is to push forward on an agreement.”

“All countries are making their own choices about how they do their negotiation,” Pershing said. “In Kyoto we brought something home that we thought would be acceptable and Congress did not accept it. We are working together with Congress to adopt something internationally that we can enact domestically. “

He added:  “We fortunately have another month for work to be done in the US and around the word. We will continue to work actively in the Senate and we think we will have the kind of information we need to move forward.”

On Tuesday in Washington President Obama essentially said the same thing after meeting with European
Union leaders. He pledged on Tuesday to redouble efforts for a climate deal, provided no details, and introduced a new way to define success at Copenhagen. “We discussed climate change extensively and all of us agreed that it was imperative for us to redouble our efforts in the weeks between now and the
Copenhagen meeting to ensure that we create a framework for progress.”

In essence the American president and his climate negotiating team are asking the world to trust them. The question in Barcelona, still not answered as day three unfolds, is whether there is enough credibiity in the U.S. position. That question won’t be answered today and likely not at this meeting. But it will be answered before the end of the year. Why?

Because two years ago leaders of nearly 200 nations committed to these diabolically difficult negotiations, buffeted by economic, ideological, and geographical impediments of every sort, in order to reach Copenhagen in December 2009 to sign a global treaty with the completely serious goal of saving the world.

In a series of negotiating sessions, periodically convened since in places like Bangkok, Bonn, Bali, and Barcelona, the basic outlines of the plan have indeed taken shape and they are apparent in Barcelona. The limits that developed countries are willing to put on carbon pollution that causes climate change is now common knowledge. The dimensions of the technological changes that are necessary to completely alter how the world powers itself have come into clearer focus. The magnitude of the cost of making the transition to a new epoch have been calculated. And there is general agreement that the wealthy nations that burned all that carbon-rich fuel have financial responsibilities to the developing countries that want to get cleaner and economically greener.

The process is being helped and hindered because the clock is ticking. There are just three more days here, and 29 more until Copenhagen for the parties to this treaty writing process to tie all of the various strands into a rope strong enough to haul the world away from peril and into an entirely different era where the quality of the environment and the strength of the economy are one and the same.

“Copenhagen must open the door to the common good and close the door to human disaster,” said Yvo de Boer, executive secretary of the United Nations Framework Convention on Climate Change, who is overseeing the negotiations. “Barcelona is essential to putting the architecture in place. This will not be a spectacular session, but it will be an important one.”

Success in the Barcelona meeting, say delegates and climate advocates, means more clearly defining which nations will put less carbon into the atmosphere, how it will be done and who will pay, shaping new markets, agreeing to monitor and enforce new rules, sharing clean energy and pollution control technology, making available energy efficiency practices. It also means agreeing to an effective system to help vulnerable regions like Bengladesh and most of Africa cope with the changing climate. And most importantly it means gaining a legally binding pact that commits nations to do what they said they’d do.

Very plainly, if all that and about a hundred other details gain more definition in Barcelona, the participating countries would have cooperated in a way that the nations of the world are just not accustomed to. And more importantly Copenhagen could be the moment and the place that countries either sign — as most countries want to do– or agree to make progress toward completing — as the U.S. prefers — what is generally considered the most complicated, confounding, necessary, and expensive international agreement ever considered.

“This is the moment of truth when the world decides whether it is committed to solving climate change or just playing theater,” said Kim Carstensen, leader of the World Wildlife Fund’s Global Climate Initiative. “We’ve been dismayed by statements that there is too little time left. We insist that we have the time to develop a binding outcome, to achieve emissions reductions, to show action on developing countries, finance, and institutions. We have the public will.”