The announcement by the Norwegian Nobel Committee in October 2009 that Barack Obama had won the Peace Prize came as a surprise to just about everyone, including the recipient. The president, barely nine months into his new job, knew that the award was an encouragement of his aspirations, not recognition of his accomplishments. He said as much in accepting the prize at the Oslo ceremony two months later. Over the ensuing three years, Obama negotiated a new strategic arms treaty with Russia, made progress in stamping out the high command of Al Qaeda, and coped deftly with "black swan" events like the Arab Awakening. But on two challenges of existential importance, he has come up short: strengthening the global nuclear non-proliferation regime and leading an international effort to slow the process of climate change. Obama had given priority to both goals in his 2008 campaign and first inaugural address but was thwarted on both, largely because of partisan opposition in Washington.