The Earth Day merrymakers who gathered in the MAC Quad on Saturday had more to celebrate than spring’s first dosage of balmy weather: Over the past year, Al Gore ’69 had won an Academy Award for his documentary “An Inconvenient Truth,” Governor Schwarzenegger had put regulatory teeth behind carbon controls, and the Supreme Court had scolded the Environmental Protection Agency for its indifference to carbon emissions. The wall of obstructionism that has long faced climate change activists has begun to crumble, or at least crack.

Oh, and one more thing: the event was co-sponsored by the Harvard Republican Club.

But that shouldn’t be too surprising. Since 9/11, environmentalists have found an unlikely ally with security hawks. Aware of the money trail coming from Saudi oil-lined coffers to radical madrassas, no self-respecting patriot can fill up at the gas pump with a clean conscience. More SUVs mean not only more floods and hurricanes, but terrorists as well. Neo-conservatives wring their hands in dismay, as the oil-rich regimes of Sudan and Iran have proved resilient to American pressures. Oh, how much bigger a stick we could wield if only America could rid itself of “dependence on foreign oil.”

Tom Friedman, in his rambling April 15 article in the New York Times Magazine, sees promise in this “geostrategic, geoeconomic” green movement. A testosterone injection will transform the stereotypical environmentalist from effete tree-hugger into gun-toting patriot. Picture it now: Dick Cheney, a card-carrying member of the Sierra Club. And many environmentalists might accept this recasting as well. They recognize that another terrorist attack strikes fear in a way that, say, melting icecaps just don’t. Clean energy, now cast in a muscular light, can be supported by conservatives—and, hopefully, lead to lower carbon emissions.

Yet the union of these two issues has not always been a harmonious one. The four-year wrangling over drilling in the Arctic National Wildlife Refuge (ANWR) is a case in point. Despite ANWR’s limited oil reserves, many Republicans viewed drilling as a question of national security: a year of our own oil was better than buying it from the Saudis. Democrats and a few Republicans wanted to leave it untouched and support cleaner energies. A similar divide emerged in the 2005 Energy Bill. Trumpeting the legislation’s promise to reduce America’s oil dependency, its authors merely showered subsidies on domestic oil, nuclear, and gas companies. Little was done to actually reduce greenhouse gases.

Some might be willing to tolerate this tenuous alliance. In the polarized Bush era, common ground is scarce. It should be heartening, then, that ideological opposites can unite behind common causes—like more wind and solar power—even if its for contrary reasons. So what if a Hollywood director and a four-star general think differently, as long as they both drive Priuses at the end of the day?

But the divide is deeper and more troubling. Back in January, the newly elected Speaker of the House, Nancy Pelosi (D-Calif.), when unveiling a Select Committee on Energy Independence and Global Warming—named in the spirit of bipartisanship, no doubt—gave it this benediction: “The science of global warming and its impact is overwhelming and unequivocal.” But then last Wednesday at the committee’s inaugural meeting, Rep. Jim Sensenbrenner, the ranking Republican, countered: “One area where there is no scientific consensus…is the effects of climate change.” Common ground is scarce indeed.

Time has come to end this relationship; national security has been wearing the pants for too long. This is already the case with the ethanol orgy in the Midwest. Despite the fact that corn-derived ethanol only yields 30 percent more energy than is required to produce it , a splurge of federal subsidies have brought about the largest acreage since 1944. And what’s more, the average American probably thinks this is a good thing.

The sooner this partnership is ended, the better, for the two groups are unlikely to agree over the next step. The current boom in clean energy investment will only be sustained if the price of oil remains high. Cellulosic ethanol, produced from trees and shrubs, promises energy yield ratios of 16, but requires extensive research into cheaper enzymes. A full-scale carbon tax would help, but hawks reject such action as quite rash. At most, they might support a gasoline tax as a way of weaning America off Saudi crude.

Unfortunately, in the battle for Americans’ hearts and purse strings, hawks still have an edge. But not for much longer. One more Katrina, and instant energy independence will hardly be the most pressing raison d’être for stringent energy standards. In the meantime, the concern should shift from one of barrels of oil imported to tons of CO2 emitted.

One way to justify this move is to link up emissions with long-term—as opposed to short-term—security concerns. Climate change offers its own chilling set of bogeymen. The developing world is predicted to bear the brunt of climate change’s maladies, as rising temperatures exacerbate food shortages. The list of failed states will be a lot longer in 20 or 30 years if no action is taken. The prospect of millions of refugees, incensed at decades of American apathy, is scary enough to keep Pentagon planners up at night.

But, alas, protecting America against these dangers requires not only accepting the science behind global warming, but taking its global consequences seriously. And hawks like Sensenbrenner are not to be trusted until they do both.

Will Johnston ’08 is a social studies concentrator in Adams House. His column appears on alternate Wednesdays.