Colombian senator Piedad Córdoba,[7][8] Afghanistan's Sima Samar,[7] Chinese dissident Hu Jia and Prime Minister of Zimbabwe Morgan Tsvangirai had been speculated to be favorites for the award.

The winner was chosen unanimously on October 5,[9] but was initially opposed by the Socialist Left, Conservative and Progress Party members until strongly persuaded by Jagland.

[11] The New York Times reported that Jagland shrugged off the question of whether "the committee feared being labeled naïve for accepting a young politician's promises at face value", stating that "no one could deny that 'the international climate' had suddenly improved, and that Mr. Obama was the main reason... We want to embrace the message that he stands for.

[13] In remarks given at the White House Rose Garden on the day of the announcement, Obama stated, "I do not view it as a recognition of my own accomplishments but rather an affirmation of American leadership on behalf of aspirations held by people in all nations.

He said those common challenges included the goal of eliminating nuclear weapons (which he said might not occur in his lifetime), nuclear proliferation, climate change, tolerance "among people of different faiths and races and religions", peace between and security for Israelis and Palestinians, better social conditions for the world's poor, including "the ability to get an education and make a decent living; the security that you won't have to live in fear of disease or violence without hope for the future."

The United States, he said, is "a country that's responsible for ending a war and working in another theater to confront a ruthless adversary that directly threatens the American people and our allies.

"[14] The award, he said, "must be shared with everyone who strives for justice and dignity—for the young woman who marches silently in the streets on behalf of her right to be heard even in the face of beatings and bullets; for the leader imprisoned in her own home because she refuses to abandon her commitment to democracy [referring to Aung San Suu Kyi]; for the soldier who sacrificed through tour after tour of duty on behalf of someone half a world away; and for all those men and women across the world who sacrifice their safety and their freedom and sometime their lives for the cause of peace.

Peter Beinart of the Daily Beast called the decision a "farce",[27] while Noam Chomsky said: "In defense of the committee, we might say that the achievement of doing nothing to advance peace places Obama on a considerably higher moral plane than some of the earlier recipients".

A Wall Street Journal editorial, noting Obama's comment that the world's problems "can't be met by any one leader or any one nation", opined, "What this suggests to us—and to the Norwegians—is the end of what has been called 'American exceptionalism'.

"[30] According to The Washington Post news analyst Dan Balz, "[E]ven among his supporters there was a sense of surprise and even shock on Friday [the day of the announcement], a belief that the award was premature, a disservice and a potential liability.

[38] James Taranto wrote in The Wall Street Journal an article summarising various opinions on the Internet, concluding how the award was embarrassing for Obama.

[40] Slate magazine blogger Mickey Kaus,[41] The New York Times columnist David Brooks[42] and former U.N. ambassador John Bolton[43] amongst others, called for Obama to not accept the award; pundit Michael Crowley argued that it was a "mixed blessing".

[20][45] Opponents of the award cite the expansion of the War on Terror and the large increase in the number of drone strikes carried out under Obama, specifically in Pakistan.

[51] RNC chairman Michael Steele discussed his disapproval of the award in a fund-raising letter, writing, "the Democrats and their international leftist allies want America made subservient to the agenda of global redistribution and control.

[58] Torstein Dahle, the leader of the far leftist party Red, called the award a scandal, citing the fact that Obama was the commander-in-chief of a country at war in Iraq and Afghanistan.

Several Nobel Laureates commented: Bangladeshi economist Muhammad Yunus (co-winner 2006 prize) said the committee's award was "an endorsement of [Obama] and the direction he is taking".

"We are entering an era of renewed multilateralism ... President Obama embodies the new spirit of dialogue and engagement on the world's biggest problems: climate change, nuclear disarmament and a wide range of peace and security challenges.

[67] Dmitry Medvedev, then-president of Russia, said the award would encourage warmer U.S.–Russian relations, and he hoped it would "serve as an additional incentive" for both governments to foster a better "climate in world politics".

[68] Hope that the prize would assist Obama's efforts toward nuclear disarmament was also a part of congratulatory statements from Ireland's Taoiseach Brian Cowen and German Chancellor Angela Merkel.

[69][70][71] Kosovar President Fatmir Sejdiu congratulated Obama by saying, "This award is testimony to your success as a leader of a free country aimed at creating a safer and more peaceful world.

"[2][76][77][78][79] Indonesia's Masdar Mas'udi, deputy head of the Islamic organisation Nahdlatul Ulama, praised Obama's policy towards his country as confirmation of his worthiness as a Nobel laureate.

[81] In Latin America, former Cuban president Fidel Castro called the award "positive" and said the prize should be seen as a criticism to the "genocidal policy" carried out by past U.S.

"As President Hugo Chávez said at the United Nations, (the Obama administration) is a government that has raised expectations and hopes in many people in the world, amid great contradictions.

[89] In 2011, Bolivian president Evo Morales and Russian Liberal Democratic Party leader Vladimir Zhirinovsky condemned the award, calling it hypocritical in light of US policy during the Libyan Civil War.

[99] Conservative The New York Times columnist Ross Douthat called it an oftentimes impressive speech that was "An extended defense of using realist means in the service of liberal internationalist ends".

[101] To say that force is sometimes necessary is not a call to cynicism – it is a recognition of history; the imperfections of man and the limits of reason.Former Jimmy Carter speechwriter Hendrik Hertzberg said that the speech "will live on for a long time as a text for peacemakers in power".

[103] A few commentators were more critical, with former US Ambassador to the UN John Bolton calling it "pedestrian, turgid, and uninspired"[104] and US Congressman Dennis Kucinich "Once we are committed to war's instrumentality in pursuit of peace, we begin the Orwellian journey to the semantic netherworld where war is peace..."[105] The New York Times praised the eloquence of the speech, noting that "President Obama gave the speech he needed to give, but we suspect not precisely the one the Nobel committee wanted to hear.

"[106] The Wall Street Journal echoed this sentiment and congratulated Obama for defending the occasional necessity of war and for stating that evil exists in the world, though used the same editorial to criticize him for current disarmament talks with Russia and a lack of progress with Iran and North Korea.

[108][109][110] Abroad, British historian Simon Schama said of the speech that "in its seriousness, bravery and clarity, [it] was on a par with FDR and Churchill" and "summoned the spirit of Cicero".

[111] President Obama reduced the number of United States Army soldiers fighting in Afghanistan and Iraq, but expanded the use of unmanned air-strikes on these countries, as well as Pakistan, Yemen, Syria, Libya and Somalia.