Fox News: In an effort to combat global warming, Al Gore has called on the U.S. to end its addiction to fossil fuels by transitioning to 100% clean energy within a decade. Is this our “man on the moon” moment, or an unrealistic pipe dream only made less likely by the current economic calamity? Clean technology experts and advocates lauded Gore’s goal as “ambitious” and something to strive for, but also said it’s widely unlikely to be achieved given a wide range of obstacles, including the …