Last weekend, up to 50,000 people rallied in Washington, D.C. to protest the creation of the Keystone XL pipeline and the expansion of the tar sands industry. This was the largest climate rally in history, and for good reason. People are finally realizing that society cannot continue to extract new forms of fossil fuels if they care at all about future generations on this planet.

Unfortunately, former Harvard president and current professor Larry Summers didn’t get the memo. In a recent Washington Post opinion piece titled “The growth agenda we need,” Summers lays out a detailed four-point plan to kickstart the American economy—a plan that includes approving Keystone XL. Summers is right in saying that it is time to transform the North American energy sector. But Summers’ plan is far from transformative. Instead, it merely reinforces the dominance of fossil fuels, an energy source that is warming our planet to unprecedented levels.

Summers claims that the U.S. must approve Keystone XL in order to keep tar sands from being exported to Asia, which has far fewer sound environmental regulations. This argument is flawed for two main reasons.

First, it makes the assumption that the morality of our nation is relative to the behavior of other nations. This relativistic viewpoint ignores the simple facts. Burning Canadian tar sands will accelerate the dangerous effects of fossil fuels and climate change, regardless of who does it. Such environmental negligence would threaten 100 million lives by 2030. The World Bank has stated that “adaptation may not be possible” to the world we are currently on track to create. It is hardly an excuse to say that we can commit deadly sins simply because the sins of others might be worse.

The second flaw in Summers’ argument is his assumption that tar sands will continue to be extracted regardless of our behavior. Tar sands can only be transported out of the heart of Canada by three routes: south, through the Keystone XL, west, through the Canadian Rockies and First Nations lands, and east, through New England. And opposition against tar sands expansion has already shown the potential to be an unstoppable force.

Thousands of people have put their bodies on the line to stop expansion to the south. Many have been arrested at the Tar Sands Blockade in Texas. Last fall, 12,000 rallied and 1,253 were arrested in Washington, D.C. to stop Keystone XL, in the largest showing of civil disobedience in 30 years. First Nations peoples of Western Canada have been steadfast in their opposition, and their enhanced legal status gives them a virtual veto over the construction of pipelines on their ancestral lands. Here in New England, Better Future Project and 350.org are working in coalition with other local and national groups to prevent ExxonMobil from shifting the direction of an oil-bearing, 60 year-old pipeline to allow it to export the heavier and more leakage-prone tar sands without the necessary presidential permit. Just two weeks ago, our groups convened over 1,500 people in Portland, Maine as the first potent display of grassroots opposition to this eastern pipeline.

We need a transformation of our energy system, as Professor Summers notes. But this transition must break away from increasing fossil fuel consumption. To some it may seem like the forces of the tar sands industry are too powerful to be stopped. But there are more people fighting for a clean energy future than ever before, and our numbers are growing every day. Our society has reached a point where we can begin to understand a world destroyed by carbon fuels, and we know that this is not a path we should begin to go down.

Rachel Carson said, “We stand now where two roads diverge. But unlike the roads in Robert Frost’s familiar poem, they are not equally fair. The road we have long been traveling is deceptively easy, a smooth superhighway on which we progress with great speed, but at its end lies disaster. The other fork of the road, the one less traveled by, offers our last, our only chance to reach a destination that assures the preservation of the earth.”

The two paths are clear before us. Which one will you choose?

Chloe S. Maxmin ’15, a Crimson editorial writer and co-coordinator of Divest Harvard, is a social studies concentrator in Mather House. Craig S. Altemose is a 2010 alumnus of Harvard Law School and Harvard Kennedy School and the Executive Director of Better Future Project.