Earth Day's slogan, "Think globally, act locally," has two implications, one physical, one mental. The easy physical stuff may ease guilt and give a sense of superiority, e.g., planting a tree, riding a bike to work or buying organic food. These are largely symbolic acts that make little difference unless they presage massive behavioral shifts.

Far tougher local actions include ground-thumping work such as fighting noxious, invasive weeds. This is an unglamorous, nasty, endless task. Thus, few of the mainstream Green groups mobilize their members to counter this pervasive threat. It's far easier to protest drilling in ANWR than to pull leafy spurge or spotted knapweed.

But here's the tough mental part: improving your understanding of how the world works. Errors and sloppy thinking come at the expense of the environment and poor people around the world. A prime example: the belief that most environmental problems are due to modernization or affluence.

In fact, across time and cultures technological advances and increased wealth have improved, not reduced, environmental quality. Consider a compelling example. The U.S. has a $9 trillion economy with a population of roughly 285 million.. China has a $1 trillion economy spread over about 4.5 times as many people. In the U.S., air particulates declined 65 percent from 1970 to 1998; toxic releases fell by nearly half between 1988 and 1998; and since 1980, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead emissions have all decreased. While the U.S. economy in 1999 was more than 30 percent larger than in 1991, carbon dioxide emissions per dollar of GDP were about 85 percent of their 1991 level. China, however, is a relative wasteland of pollution. NASA images have shown the eastern part of the country cloaked in a brown smog, with the capital Beijing obscured under a dense haze of pollution.

Earth Day has been relevant mainly to people in the developed world. It's easy to see why. Almost half of the world's people live on less than $2 a day; a fifth live on less than $1. Under such conditions, these folks spend most of their resources on simple subsistence. At this income level, a clean environment is a luxury they cannot yet afford. We find this depressing. But some nations have made significant gains in reducing poverty. And with reductions in poverty come all sorts of social benefits, e.g., higher life expectancy, lower infant mortality, better education, and a cleaner environment. How does this happen? Successful countries institute real economic reforms. These include limiting government spending, sound monetary policy, and removing governmental economic controls (e.g., on wages and prices).

They also do one other crucially important thing - they open their economies to the global marketplace. Globalization provides access to foreign capital, export markets, and advanced technology while breaking the monopoly of inefficient and protected domestic industries. Only countries that have entered the global economy have been able to raise their living standards. Knowing this, there seems to be a conspiracy in the developed world against the poor. Blaming Third World environmental and human rights abuses on "globalization," many in the U.S. want to arrest the spread of free markets.

Labor unions and some "Naderite" environmental groups have joined forces. (Remember the "Teamsters and Turtles" marching through the streets of Seattle during the anti-globalization riots?) In a strange twist, these self-proclaimed "progressives" are bolstered by unlikely allies such as isolationist conservative Pat Buchanan. What explains their motivations? Often their arguments are based on the myth that nations are engaged in a "race to the bottom," i.e., they sacrifice environmental quality and labor standards for economic gain. But the available evidence refutes this thesis. Nations with low standards do not gain a larger share of foreign direct investment or export markets. In fact, the large majority of the world's trade and foreign investment flows among advanced economies with high environmental and labor standards.

Trade barriers deprive poor countries of the opportunities they need to raise overall living standards. Export industries in less-developed countries usually pay the highest wages and maintain the highest working standards. Trade restrictions hurt them most. These well-intended acts shift activities to areas where people and the environment are more easily exploited.

If we really want to celebrate Earth Day, let's make sure the U.S. resists further protectionism and encourages free trade for all, so that poor countries can develop more rapidly. Economic progress is the surest way to improve labor and environmental standards.