GUATEMALA CITY — A U.N. summit on climate change at the recent U.N. General Assembly meeting was supposed to give momentum for a post-Kyoto Protocol accord to be penned in December in Copenhagen. Indeed, an announcement was made that most leaders agreed that there is an "urgent and significant need" to cut greenhouse gas emissions.

But even though most participants accept a controversial claim that human-based carbon emissions cause climate change, they are unlikely to agree to significant curbs. And if such an accord is reached, it is unlikely to be implemented, not even by those countries that supply the most vocal and ardent supporters.

While the United States drew international criticism for not adhering to the Kyoto Protocol, from every performance and compliance standard, most countries that signed on did not fulfill their promises.