NASA’s James Hansen tried this week to surf the 20th anniversary of his famous congressional testimony that launched global warming hysteria. Apparently not wanting to be left out of the green hoopla, John McCain tried to catch Hansen’s wave.

Both wiped out with embarrassing proposals.

You might have thought that Hansen’s main talking point this week would have been, "See, I was right." But, of course, he wasn’t, so he couldn’t take any credit.

With 20 years of real-life data to compare against Hansen’s 1988 predictions, it’s clear that reality has way underperformed on his fantasy of carbon-dioxide-stoked warming.

No doubt this is in large part due to Hansen’s yet-to-be-validated assumption that manmade CO2 emissions drive global climate in a meaningful way.

Hansen has been so far off the mark in forecasting global warming that he seems to have forsaken it altogether in favor of simply declaring that atmospheric CO2 levels must be reduced from the current level of about 380 parts per million to less than 350 ppm "to preserve creation, the planet on which civilization developed."

But there is no scientific analysis to support 350 ppm or any other specific target as the preferred level of atmospheric CO2; moreover, 350 ppm also is not something likely to happen in our lifetimes no matter what we do.

The U.N. Intergovernmental Panel on Climate Change projects that atmospheric CO2 concentrations will climb to around 700 ppm if no action is taken to curb CO2 emissions as compared to around 500 ppm under a maximum regulation scenario. Some in the alarmist community doubt that the latter level can be achieved without dramatic and as-yet-unimagined advances in technology.

Bereft of science, Hansen was left to do what he does best — act the drama queen, as he did in 2006 when he likened the Bush administration to Nazi Germany and the Soviet Union for reviewing his public presentations before he made them.

"CEOs of fossil energy companies know what they are doing and are aware of the long-term consequences of continued business as usual. In my opinion, these CEOs should be tried for high crimes against humanity and nature," Hansen said this week.

"Since his appearance on the Hill 20 years ago, Hansen had lost most of his hair; the few remaining strands, suspended over his head by static electricity or some other force, gave him a crazy-professor look," the Washington Post’s Dana Milbank reported after Hansen’s encore performance.

Hey, Dana, it might not just be a "look."

Meanwhile, John McCain, who fancies himself as the taxpayer’s knight in shining armor, tried to color himself green by proposing to gouge taxpayers for CO2 emission reductions that may never happen.

Earlier this week, as part of his proposal that taxpayers award $300 million to the developer of the next generation auto battery that would leapfrog hybrid and electric car technology, McCain also proposed that auto manufacturers be given a $5,000 tax credit for every zero-emissions vehicle they sell.

But when you do the math, McCain’s proposal turns out to be little more than a taxpayer rip-off in favor of ZEV makers.

Given that the average car emits about 6 tons of CO2 annually and has a lifetime of about nine years, replacing a regular car with a ZEV would eliminate about 54 tons of tailpipe CO2 emissions. With the tax credit, this works out to taxpayers paying ZEV makers about $92.60 per ton of tailpipe CO2 emissions avoided.

A cheaper way to reduce CO2 emissions, however, would be to purchase carbon credits on, say, the Chicago Climate Exchange, where they cost about $5.30 per ton – more than a 94 percent savings over the McCain plan.

Additionally, these credits can be purchased and emissions could be reduced now — which would make Hansen happy — rather than at some future point if ZEVs ever catch on with consumers.

Keep in mind that General Motors cancelled its ZEV program in 2003 because it could not sell enough of the vehicles to make it profitable. Despite the millions of Americans who either belong to or donate to environmental groups, GM only sold about 1,100 ZEVs after spending about $500 million to develop the vehicle.

Adding insult to injury is the illusory nature of ZEVs.

Even if they caught on with consumers, it’s not clear they would meaningfully reduce CO2 emissions. While CO2 wouldn’t be emitted from ZEVs, it would be emitted from the smokestacks of the power plants supplying the electricity used to charge ZEV batteries.

Later in the week, McCain proposed to green the government by buying more fuel-efficient vehicles. But while fuel-efficient vehicles certainly exist, they tend to cost much more than the fuel savings they produce.

Hybrid cars aren’t cost-effective unless gas costs around $10 per gallon or the cars are driven more than 65,000 miles per year. FedEx Corp., owner of the largest fleet of hybrid trucks, has publicly admitted that the trucks aren’t cost-effective. The cost of Santa Clara, Calif.'s fuel cell buses is a staggering $51.66 per mile as compared to $1.61 per mile for a diesel bus.

Perhaps McCain should put his money where his mouth is and get a fuel cell model for his Straight Talk Express campaign bus. Let’s see if he’s willing to spend his limited campaign funds living up to his own proposals.

Steven Milloy publishes JunkScience.com and DemandDebate.com. He is a junk science expert, advocate of free enterprise and an adjunct scholar at the Competitive Enterprise Institute.