A nation that promises a sport utility vehicle in every driveway is not a nation prepared to do anything but talk tough about air pollution. Vice President Gore started his trip to Kyoto barely willing to do even that, instead offering a confusion of proposals he called “flexibility.” These ultimately meant the United States followed, rather than lead, the rest of the industrialized world in reducing air pollutants.

This is not to belittle Mr. Gore’s challenge: It can’t be easy to negotiate an international agreement on a controversial subject while U.S. senators appear on talk shows to promise that nothing the vice president agrees to will survive Congress. It is probably even harder for Mr. Gore to do this while simultaneously running for president.

At least the proposal the vice president brings back to the United States is more substantial than what he carried to Japan, which included a 2 percent reduction in 1990 greenhouse gas levels by 2012, but it still does not reflect the Clinton administration’s professed interest in this issue or the vice president’s personal commitment to environmental matters.

Kyoto participants agreed, essentially, to split the difference between the U.S. and European positions on pollution reductions, but scientists observing the talks quickly pointed out that, with the current rate of carbon dioxide emissions from fossil fuels, concentrations of greenhouse gases in the atmosphere are expected to continue to increase over the next 30 years.

If the administration had been serious about making real progress through the Kyoto conference, it would have put far more effort into explaining the dangers of climate change, dispelling myths about it and answering critics who see the subject as nothing more than a conspiracy between the environmental community and one-world-government types. The United States is the world’s largest contributor of greenhouse gases — losing that honor is not a simple matter of political will.

Yet the U.S. contribution to Kyoto is very much in keeping with the administration’s environmental strategy of talk globally, act incrementally. From the logging loopholes in the Northwest’s Option 9 to the White House’s reluctance to support the EPA’s new Clean Air Act proposals, the president and vice president have treated supportive environmentalists shabbily.

Vice President Gore returns from Japan with a European plan, little support in Washington and a public still trying to understand the science of global warming. The fight he faces with Congress, in part, is of his own making.