NBC: Thousands of protesters took to the National Mall on Sunday for a climate rally that organizers touted as the largest of its kind in U.S. history. The group's top priority was to urge President Barack Obama to reject the proposed Keystone XL pipeline that would carry tar sands from Canada through the United States.
"When you are in a hole stop digging. Above all, stop the keystone pipeline. The president can do that with the stroke of his pen,' said Bill McKibben, founder of the environmental...