Among the chief barriers to a comprehensive deal in Copenhagen is Congress’s inability to enact climate and energy legislation that sets binding targets on greenhouse gases in the United States. Without such a commitment, other nations are loath to make their own pledges.
The chief American climate negotiator, Todd Stern, has said that he will not go beyond what Congress is willing to endorse. His deputy, Jonathan Pershing, affirmed this last week at a negotiators’ meeting in Bangkok. “We are not going to be part of an agreement we cannot meet,” Mr. Pershing said.
Administration officials and Congressional leaders have said that final legislative action on a climate bill would not occur before the first half of next year.
European officials have been pressing hardest for some form of binding treaty modeled on the Kyoto Protocol of 1997, which the United States refused to ratify because, American officials said, it imposed emissions limits on developed nations while demanding nothing of rapidly growing economies like China and India.
American officials have said that no agreement in Copenhagen is better than a bad deal that cannot be ratified or enforced. And they note that it took four years after the initial negotiation of the Kyoto accord to complete it.
There is general agreement among international negotiators and knowledgeable observers that the parties to the Copenhagen talks, held under the auspices of the United Nations Framework Convention on Climate Change, will agree to continue discussions next year, and perhaps set a deadline for reaching a final agreement by midyear or December 2010 at the latest.
The rest of the outcome, even the form it may take, remains uncertain. The world’s biggest economies agreed at a meeting last summer in L’Aquila, Italy, on a goal of limiting global temperature increases to about 2 degrees Fahrenheit above current levels, though they did not agree on the means to get there or on how to enforce it. Such a goal is expected to be part of any declaration from Copenhagen.
International climate negotiations for a global climate treaty are not producing the required results in the given amount of time left before the Copenhagen conference in December, diminishing the hopes for a resolution at this conference.

Global mean surface temperature difference from the average for 1961–1990 
Major polluters have already decided that the only way for a plan of this scale to take effect is to have steps towards the reduction of greenhouse gases instead of creating a plan which takes immediate effect and shuts down production facilities.  Countries are likely to propose steps at the Copenhagen Meeting.

Yvo De Boer, a Dutch Diplomat, has been overseeing the proceedings so far. "There isn't sufficient time to get the whole thing done. But I hope it will go well beyond simply a declaration of principles. The form I would like it to take is the groundwork for a ratifiable agreement next year," commented Boer.

The 192 countries which make up the United Nations show the gaps in-between their ideas. Wealthier nations are planning to help poorer countries with enforcing climate laws and investing in newer technology. 16 of the largest polluters have already begun planning on aiding poorer countries.

Officials are attempting to narrow down issues which countries agree on, such as certain steps and the common goal to limit emissions. Negotiators plan to discuss how the treaty will be upheld at Copenhagen. Diplomats have raised the question of reliability, since most of the supporting countries have not enforced any binding climate legislation within their own countries. Until it is shown that all countries participating will uphold the treaty, nations are unwilling to enforce a treaty within their own country.

Although there are hopes of progress in Copenhagen, observes note that radical change is unlikely. "The most likely form any agreement will take will be a political declaration," said Nigel Purvis, State Department climate negotiator during the Clinton Administration and Bush administration.