President Obama stood up to Big Oil and its puppets in Congress and denied a permit for the Keystone XL tar sands pipeline yesterday. This is encouraging news for the communities whose air and water would have been directly threatened by this pipeline, from Canada to Nebraska to the Gulf Coast. And it's an important piece of the struggle to avert a runaway climate catastrophe. But since the Keystone XL has become a pitched political battle, this announcement is also an encouraging affirmation of the power of people, creative protest, and grassroots organizing in the face of the entrenched power and big bucks of the oil industry.

The pen is mightier than the sword, but the purse may sometimes be mightier than the pen. Major US corporations are adding market pressure to the growing wave of opposition against tar sands expansion, giving tar sands producers a fresh reason to consider the consequences of their poor environmental street cred.

Whole Foods Market and Bed Bath and Beyond joined a list of six major Fortune 500 companies, including Gap, Timberland and Levi Strauss, committed to reducing or eliminating tar sands oil from their businesses. Walgreens also recently announced it will avoid purchasing tar sands oil to fuel its distribution network.