“I’m expecting that Sunday will be the biggest rally about climate change that there’s ever been in this country,” Bill McKibben says about this Sunday’s #ForwardOnClimate rally in Washington, DC. What will it take to stop the Keystone XL pipeline, according to the 350.org founder? “We’re not going to outspend the fossil fuel industry,” he explains. “We have to find other currencies to work in, and those are the currencies of movements.”

—James Cersonsky

McKibben was one of 50 activists arrested for chaining themselves to the White House gate on Wednesday. Read George Zornick’s report on what went down.