Earlier this year, I attended a multidenominational service in San Francisco, the "Gathering of Hearts." It brought together the Dalai Lama, the world's most prominent nontheistic spiritual figure, and the leaders of three sects--Sunni, Shia, and Sufi--of the world's most assertively monotheistic faith, Islam. They were joined by the Episcopal dean of Grace Cathedral, prominent Jewish rabbis, a member of the Grand Council of the Iroquois Confederacy, and a Hindu nun.

I was struck, during the course of that afternoon, by how this effort at interfaith dialogue was impelled by more than the desire to overcome internecine misunderstanding and conflict. These visionary leaders were also grappling with the fundamental spiritual crisis that challenges all the world's faiths. It is, they said, as though a sinister new religion were sweeping the earth: Its God is Mammon, its temples shopping malls, and its altars constructed of dollars, euros, yen, and rupees. As for its teachings, they consist of a sole commandment: "Buy more."

In the struggle against this consumerist creed, warned one speaker, "time is not on our side. The world's religions need each other." The message struck home because the same old sins that challenge religion--greed, pride, and gluttony--are also at the root of the environmental crisis. Time is not on humanity's side in this struggle either. While we scramble to gain critical knowledge about how we affect the natural world, its systems are changing before our eyes. Meanwhile, our resources are limited, our technology imperfect, and we don't even agree on what it is we value. Wilderness or comfort? An easy life for us or an intact world for our children? We broadly agree--rhetorically, at least--that we should be on a path to sustainability, yet instead we are on a path to disaster.

Why? Because sustainability is about planning for the future, and most of our important decisions routinely ignore it. We plan in the smallest of time scales--not for the seven generations the Iroquois would consider, not even for a saeculum, the span of an ordinary human life, but for the next election cycle, annual dividend, or quarterly return. Short-term decisions, whether individual or collective, are almost inherently selfish. The horizon Congress considers, for example, is generally limited by the (also short-term) wishes of campaign contributors or an upcoming election.

Our shortsighted global-trade rules affront the pious and environmentalist alike. In every major trade negotiation to date, both camps have suggested provisions to allow subsistence farmers to remain on their land, to get lifesaving drugs into the hands of poor people, and to protect the earth's ecosystems--all elements of a sustainable system. But in every such negotiation, those ideas have been rejected--not because they wouldn't work, but because they would work at the cost of slowing the accumulation of wealth by the world's elite. During the North American Free Trade Agreement negotiations, for example, the Sierra Club advocated a modest, 20-year border-crossing fee that could have provided frontier cities with safe drinking water, cleaned up hazardous-waste sites, and built sewers and sewage-treatment plants. The idea was rejected; 15 years later, the U.S.-Mexican border remains the world's largest toxic-waste site.

In the face of climate collapse, environmentalists have proposed numerous long-term ways to slow global warming and minimize human suffering, including the widespread adoption of hybrid motors. Instead of using hybrid technology to make their SUVs and trucks fuel efficient, however, General Motors and other automakers use it to make them bigger and more "muscular." Why? Because Detroit has made a lot of money selling big, muscular SUVs and concludes it must be ever thus.

As we are now discovering, Mammon is an unforgiving and bloody God. (The Dalai Lama put it much more gently, referring to even the most horrendous human behavior as the work of "mischievous people.") Now those of us who hold to other beliefs--whether theistic, spiritual, or simply an abiding faith in human goodness and reason--desperately need to counter the future-blind consumer cult that is robbing our children. To do so, we all need each other.

Carl Pope is the Sierra Club's executive director. E-mail carl.pope@sierraclub.org.

Photo by Lori Eanes; used with permission