Washington - In the end it was a very brief trial run. The US Congress' first real debate on tackling climate change was brought to an end only five days after it started, and a landmark bill that would have curbed greenhouse-gas emissions was shelved until next year.
But for many environmental groups, that still represented progress in a country that has been typically averse to any measures that would force companies to limit emissions that contribute to global warming.
The Climate Security Act, which would have introduced a cap-and- trade system and brought US targets on cutting emissions roughly in line with the recommendations of international scientists, had been the subject of an intense debate in the US Senate since Monday.
Republican opponents warned it would impose one of the largest ever burdens on the American public, further raising surging petrol prices and doing untold damage to an economy that is already on the brink of recession.
President George W Bush, who has long opposed mandatory limits on greenhouse-gas emissions, had threatened to wield his veto if the legislation made it to his desk.
'It's probably the largest bill ever considered by the United States Senate in terms of its impact on the economy,' Senator James Inhofe, one of its principal opponents, said ominously earlier this week.
Democrats charged that opponents were using 'scare tactics' and over-estimating the cost of the bill, which they said would help wean the United States off its dependence on foreign oil and encourage new technologies that would boost jobs in the US. They warned that allowing global temperatures to rise unhindered would be a far worse price to pay.
The Senate's raucous five-day debate was effectively quashed Friday morning by Democrats who had grown tired of a series of procedural roadblocks put in place by Republican opponents.
A motion to force the bill to a vote was supported 48-36, falling short of the 60 votes needed to prevent Republicans from pushing an endless discussion - known as a filibuster - on the floor of the Senate.
Another six senators unable to attend the Senate talks had sent messages saying they would have approved the motion, including both presidential candidates - Democrat Barack Obama and Republican John McCain.
Nobody had really expected the climate bill to pass this year, but supporters took Friday's vote as a sign of growing support for climate change legislation in the United States.
'I'm very, very ... delighted that we laid the foundation for this very important legislation,' said John Warner, a veteran Republican senator who cosponsored the climate bill.
Despite international pressure - especially from the European Union - to take a tougher line on preventing climate change, legislators in the United States have been slow to come around to the idea of mandatory emissions caps.
Contrary to popular perception, Bush was not alone in opposing the Kyoto Protocol, an international treaty that for the first time imposed targets on developed countries to reduce their emissions levels.
The Senate, in a non-binding vote, opposed the Kyoto Protocol by 95-0, shortly before it was signed by former president Bill Clinton in 1997. Kyoto was never formally submitted for ratification.
Given that background, the mere fact that global warming was debated in Congress this week - and Friday's vote - was viewed as a sign of just how far things have come.
'The Climate Security Act made history as the first comprehensive stand-alone global warming bill to reach the Senate floor,' said Frances Beinecke, president of the National Resources Defence Council.
'Once we have a new president who shows real leadership on global warming, defenders of the status quo will no longer be able to thwart the publics desire for change, as they did today,' he said.
Obama and McCain have both said they support a cap-and-trade system, which allows companies to buy and sell pollution allowances allocated to them by the government. A similar programme already exists in the EU.
Supporters are pressing for a quick approval of emissions curbs in 2009, allowing the US to regain the upper hand ahead of a major end- of-year summit in Copenhagen, where governments plan to negotiate a successor to Kyoto, which expires in 2012.
'We're going to pass a bill next year. I am absolutely convinced of that,' said Senator John Kerry, the Democrats' 2004 presidential candidate. 'This was the forerunner, and I think everybody ought to be very proud of it.'
© Deutsche Presse-Agentur
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