With Prime Minister Blair making global warming one of his top priorities for the G-8 summit meeting, Europeans’ sense of moral superiority could hardly be higher. While the Kyoto Protocol nations have promised to take dramatic steps to stop global warming, America stands alone as a pariah on the world stage.

But is it that simple? Hardly. There are two major issues of debate on climate change, and on both fronts the story is far more complicated than it appears.

First is the question of the scientific consensus behind the idea that man-made greenhouse gas emissions are the sole cause of global warming. Environmental advocates are adamant on this point, and European scientists have taken to calling American skeptics “creationists.” This is sadly misleading.

Here’s the plain truth: There is significant evidence that human actions may well be a major factor in global warming – but it is not conclusive, and there are still fundamental questions to be answered. As the National Academy of Sciences has put it, there is a “wide range of uncertainty inherent in current model predictions of global climate change”; consequently, “a causal linkage between the buildup of greenhouse gases in the atmosphere and … climate changes… cannot be unequivocally established.” The evidence is “suggestive of such a linkage, but it does not constitute proof.”

What European and American greens don’t understand is that admitting – indeed, focusing on – these scientific uncertainties is not a reason to do nothing; it’s our only hope for doing the right thing. The National Academy of Sciences has been clear on this point as well: “Without an understanding of the sources and degree of uncertainty, decision makers could fail to define the best ways to deal with the serious issue of global warming.” We don’t need to wait until all the science is settled before we act, but we must not think that we should stop studying the science just because we’ve begun to act.

Which brings us to the second issue that Mr. Blair doesn’t seem to understand: The solutions to global warming are far more complicated than the science. While Europeans boast of their ratification of the Kyoto Protocol, environmental advocates would be wise to recognize that there isn’t the slightest chance that Europe will actually meet its Kyoto targets.

Overall European greenhouse gas emissions are still rising; at best, they will only be cut by 1% by the end of this decade. (Meanwhile, developing world emissions will continue to grow.) The few countries that have made real progress – England, Germany, and Russia – have done so simply as a byproduct of unrelated economic trends (the United Kingdom’s shift to natural gas, and the restructuring of the Eastern European economies following the collapse of the Soviet Union).That progress will not continue. Germany, for instance, says it will be nuclear-free by 2021, which will require closing 19 nuclear power plants that currently produce 30% of German’s electricity – without emitting any greenhouse gases.

It won’t take long for the ineffectiveness of the Kyoto Protocol to become painfully obvious to all; at that point, the world will begin to think seriously about what other options we have. And the answer, ironically, may come from America. While the American approach to climate change is roundly ridiculed in the world press and public opinion, it has a much better chance of producing real solutions to this complex problem in the long run.

American policy is based on two sound principles: First, dramatic action today – cutting our emissions by 30%, as Kyoto would have required – is politically unrealistic and would only be counterproductive in the long run. Policies that undercut economic growth aren’t sustainable; indeed, maintaining strong economic growth is the only way we will be able to afford multibillion dollar investments in developing and deploying new, clean energy technologies in the coming decades.

Which is the second key element of America’s strategy: Dramatic reductions in global emissions of greenhouse gases are out of the question unless we can make major technological breakthroughs in the next 20 years. And America is leading that effort, spending $5.5 billion a year on climate change science and technology programs. This includes $1.2 billion to develop hydrogen fuel cell-powered cars, which emit no pollution at all. (We can build these cars today – but they cost $1 million each. In 15 years, if President Bush’s initiative works, we may all be driving them.)

America is also figuring out how to build the world’s first coal-fired power plant that doesn’t emit any carbon dioxide. American states are experimenting with their own greenhouse gas controls, and American companies (such as General Electric, which as recently made development of climate-friendly products a top priority) are leading the global R&D effort.

America’s approach isn’t producing drastic emissions reductions today – but it is our only hope of making real reductions tomorrow. America is doing what it does best – fostering vigorous experimentation with different approaches to meeting the climate-change challenge. This is a classic turtle and the hare story – and America’s slow and steady approach is the only way to win this race.

Mr. Thernstrom is the director of the W. H. Brady Program in Freedom and Culture at the American Enterprise Institute. From 2001 to 2003 he served as director of communications for the White House Council on Environmental Quality.