It's been a bumpy road for Lisa Jackson through three and a half years as chief administrator of the Environmental Protection Agency (EPA). But the 50-year-old chemical engineer doesn't look fazed or fed up. A scientist-turned-insider who has learned that the levers of power don't always budge without a fight, she shows a little steel in her eyes as she ticks off achievements and notes setbacks. But she also lets mischief color her laugh as she acknowledges what she calls the "toxic attitude of absolute certainty" that paralyzes progress on climate and other issues.
In 2009, President Obama appointed Jackson to lead the EPA, the agency she'd worked at for 16 years before serving in New Jersey's environmental agency, where she became commissioner in 2006. Jackson took the EPA helm at a moment of high hopes for green advocates in the U.S. They'd spent eight years in George Bush's wilderness; now they felt they were on the verge of passing climate legislation at home and a global carbon accord at the Copenhagen talks.