USA Today: In a television commercial set to air today, billionaire climate-change activist Tom Steyer is launching a fresh line of attack against the Keystone XL pipeline by questioning its economic benefits.
The 90-second ad, provided to USA TODAY in advance of its first airing, is the third in a series of four commercials Steyer has funded as part of his effort to kill the pipeline. The 1,700-mile pipeline, which would carry heavy crude oil from the tar sands in Canada to Texas refineries, awaits approval...