German Chancellor Angela Merkel's energy policy has undergone a dramatic about-face. Last fall, her center-right coalition reversed a previous government plan to ditch nuclear power. But Germany's visceral aversion to nuclear power, which has been an intricate part of German identity since the 1970s, gaining steam after the 1986 Chernobyl disaster, grew in the wake of Japan's Fukushima nuclear accident. And Ms. Merkel was swayed to wean one of the world's biggest economies off its nuclear supply. The government cemented the move in a late June vote.