As we begin the twenty-first century, the environmental discourse is showing signs of maturing. At the time of the first Earth Day, 30 years ago, most people in the business community thought environmental protection would be ruinously expensive, while many environmentalists were pessimistic that substantial improvements were possible in the coming decades. Yet major improvements came quickly. To be sure, regulation has been very expensive, but it has not been ruinously expensive in most cases.

This is not to say that none of the cost was wasteful and that particular regulatory prescriptions were optimal. Greater environmental gains might have been available through different strategies, but this policy argument will go on forever. Often the good faith cost estimates of regulatory compliance proved to be too high because the ingenuity and productivity of American business was underestimated.

The more recent experience shows that the basic economic trend of falling material and energy intensity in the production of goods and services is converging with environmental concerns in a way that was not foreseen at the time of the first Earth Day. As this report has shown, in some areas, such as air quality, we have consistent, high-quality measurements to show our progress. In other areas, we have major gaps in our data or only fragmented knowledge, and in some cases no measures of any kind. This is especially the case for wildlife habitat and biodiversity.

However, current trends suggest that environmental policy may slowly become less adversarial in character, evolving into the consensus issue it was expected to be at the time of the first Earth Day. This may mean that the radical elements of the environmental movement—those individuals and groups who reject economic growth and technological innovation—will be marginalized, as Peter Huber suggests in his recent book Hard Green: Saving the Environment from the Environmentalists.70 This can only be a positive development for those who recognize the vital link between environmental health and economic growth—and for our environment itself.