Climate change is currently the top issue at the G8, outranking the global debt or fair trade or foreign aid - see 0.7 per cent - issues, mostly because the Bush Administration ignores the science and has declared the Kyoto Protocol to be "dead" despite it being implemented already in all the other developed nations.
As of the 2005 G8 summit, diplomats were working towards a compromise where the USA would take the lead in funding adaptive technology to conserve energy, generate renewable energy, and store electricity in fuel cells. Some, notably Canadian diplomats (who often act as apologists or foils for the US in such negotiations), were promoting this as an ideal situation where, the US's "dynamic economy" would ensure that the gains soon outstripped those required by Kyoto, in part because of the long term industrial strategy that it would enable: shifting to sustainable development in all nations especially China, India and Mexico which are not part of Kyoto.
Skeptics point out that creating carbon markets where climate change gains can be directly exchanged for hard currency on a global basis, better matches the problem scope (which is global) and spurs technology development globally, not only in the US. While failing to impose carbon limits on US industry will make it difficult for Canadian industry (Kyoto-compliant) to compete in the short term, while failing to break the US of its addiction to foreign oil.
Also the technological optimism regarding the potential of the US economy to act as the innovator, may not be warranted. The US auto industry for instance has totally failed to innovate in the critical areas of transport conservation, electric motor and battery design - including fuel cells. There have been many cases of innovative technologies squelched by this industry - see General Motors and Tucker - although the worst abuses may be past.
Also, other US policies work against a serious adjustment by the important domestic market: energy subsidy to oil companies and the indirect military subsidy that controls some oil-producing nations - like Iraq, Saudi Arabia and Kuwait, help to keep oil prices artificially low. Some have estimated that the actual price of oil without this subsidy is $200/barrel.
Agreement to impose some kind of full cost accounting and potentially even monetary reform is conditional on an acceptance of some scientific basis to calculate it. This is obviously impossible if the US continues to deny science as the basis for climate policy.