"The justification for the prize, while certainly unexpected and a bit tenuous, is indeed rooted in fact. Obama has long been a booster for non-proliferation, and his speech and lobbying at the UN General Assembly and Security Council proved to be quite successful. On climate change, the Obama administration has taken the toughest line against carbon emissions of any White House so far in terms of concrete regulations by Federal agencies. The September announcement by the EPA that the agency would begin to regulate CO2 as a pollutant, verified by the Supreme Court in 2007, was a major step towards US action on the climate change issue. Though cap-and-trade or other large scale programmes are clearly the purvue of Congress, the executive branch's efforts in the realm are likely to be a major portion of the US effort. Regarding diplomacy, the committee was likely in part referring to the re-elevation of Susan Rice's post, the US Ambassador to the UN, to a cabinet level post, as well as his public addresses and promised strategic changes toward diplomatic action over rapid military decisions - such as Iran. The G5 plus one meeting with Iran, where Undersecretary of State Burns officially met with the Iranian negotiator, and found a way forward on nuclear energy processing was the first concrete outcome of this strategy." - Steven Perez from Bookmarklet