Future historians will pinpoint Democratic Sen. Harry Reid's energy legislation, released last Tuesday, as the moment that the political movement of global warming entered an irreversible death spiral. It is kaput! Finito! Done!

This is not just my read of the situation; it is also that of Paul Krugman, the Nobel laureate-turned-Democratic-apparatchik. In his latest column for The New York Times, Krugman laments that "all hope for action to limit climate change died" in 2010. Democrats had a brief window of opportunity before the politics of global warming changed forever in November to ram something through Congress. But the Reid bill chose not to do so for the excellent reason that Democrats want to avoid an even bigger beating than the one they already face at the polls.

Not only does the bill avoid all mention of an economy-wide emission cap through a cap-and-tax—oops, cap-and-trade—scheme, it even avoids capping emissions or imposing renewable electricity standards on utility companies, the minimum that enviros had hoped for. Beyond stricter regulations on off-shore drilling, it offers subsidies to both homeowners to encourage them to make their homes more energy efficient and the nation's fleet of trucks to use cleaner burning natural gas. This is not costless, but it is a bargain compared with the "comprehensive" action on energy and climate change that President Barack Obama had been threatening.

Krugman blames this outcome on—you'll never guess this!—greedy energy companies and cowardly Republicans who sold out. But the fault, Dear Paul, lies not in them, but in your own weakling theories.

The truth is that there never has been an environmental issue that has enjoyed greater corporate support. Early in the global warming crusade, a coalition of corporations called United States Climate Action Partnership was formed with the express purpose of lobbying Congress to cut greenhouse gas emissions. It included major utilities (Duke Energy) and gas companies (BP) that stood to gain by hobbling the coal industry through a cap-and-trade scheme. Meanwhile, the Breakthrough Institute, a highly respected liberal outfit whose mission is to rejuvenate the progressive movement in this country, points out that environmental groups spent at least $100 million over the past two years executing what was arguably the best mobilization campaign in history. Despite all of this, notes Breakthrough, there is little evidence to suggest that cap-and-trade would have mustered more than 43 votes in the Senate.

This means that lucre is not the only motivating force in politics. Indeed, lobbyists are effective generally when they represent causes that coincide with the will of constituents, which is far from the case here. Voters are reluctant to accept economic pain to address remote causes with an uncertain upside. Heck, they are dubious even when the cause is not so remote and has a demonstrable upside. Take Social Security and Medicare. It is a mathematical certainty that, without reform, these programs will go bankrupt, jeopardizing the health care and retirement benefits of tens of millions Americans. Even though the cost of action is far smaller compared with the cost of inaction, persuading voters to do something is an uphill battle.

Yet even in the heyday of the consensus on global warming there was never this kind of certainty. The ClimateGate scandal—in which prominent climatologists were caught manipulating data to exaggerate the observed warming—has significantly weakened this consensus. But even if it hadn't, climate change is too complex an issue to ever be established with anything approaching iron-clad certainty. Hence, it was inevitable that it would run into a political dead-end.

This is exactly what the Reid bill represents. Indeed, if Democrats backed-off from their grand designs to cut carbon emissions 17 percent below 2005 levels by 2020 with sizable majorities in Congress and a "celestial healer" in the White House there is little chance that they will ever be able to accomplish anything better at a later date. And if America—the richest country in the world and the biggest emitter of greenhouse gases—won't act, there is a snowball's chance in Mumbai that India or China will.

Of course, authoritarian countries have a little bit more leeway than democracies to push unpalatable remedies. But it is not within the power of even China's autocrats to shove an energy diet down the throat of their people on the theory that the pain from it will be short-lived because it will trigger a search for better and cleaner energy alternatives—the totality of the green pitch for action.

This doesn't mean that there aren't a few more whimpers left in the global warming movement before it finally passes. On the international front, the buzz is that the Fifth Intergovernmental Panel on Climate Change currently in the works will be even more alarmist than the previous one. However, thanks to ClimateGate, it will give greater play to alternative voices. "Going forward, the general perception won't be one of consensus," notes Cato Institute Senior Fellow Jerry Taylor, an expert on energy issues, "but one of increasing appreciation of disagreement on the issue."

Domestically, green groups will prod the Environmental Protection Agency to regulate greenhouse gas emissions more aggressively. But this will be harder to do when Republicans inevitably make gains in Congress in November. Indeed, they will likely revive a Senate resolution floated by Lisa Murkowski, an Alaska Republican, banning the EPA from regulating emissions from stationary sources, which lost by just four votes last month. Global warming warriors are also talking about fighting the battle for emission cuts state-by-state. But they will lose on that front too. California, which embraced such cuts four years ago, is already facing a ballot initiative in November to scrap the law, as it loses business and jobs to other states. Indeed, the same collective action problems that prevent global action on climate change will inevitably bedevil state-level action too.

The global warming warriors will likely have to go through the five stages of grief before accepting that their moment has passed and the movement is dead. Thinkers more sophisticated than Krugman will no doubt point to many proximate causes for its demise beyond evil Republicans such as lack of engagement by President Obama, bad economic timing, filibuster rules, what have you.

The reality is, however, that the crusade was doomed from the start because of its own inherent weaknesses. RIP.

Shikha Dalmia is senior analyst at a Reason Foundation and a biweekly columnist at Forbes. This column originally appeared at Forbes.