Reporting from Oslo — President Obama accepted the Nobel Peace Prize on Thursday as the leader of a country fighting two conflicts, using a ceremony honoring the pursuit of peace to lay out a moral justification for war.
A week after ordering 30,000 more American troops into Afghanistan, Obama told a committee that chose him to join the company of such icons of nonviolence as Mohandas Gandhi and Martin Luther King Jr. that evil must sometimes be met with force.
"Instruments of war do have a role to play in preserving the peace," he said.
"So part of our challenge is reconciling these two seemingly irreconcilable truths -- that war is sometimes necessary, and war is at some level an expression of human feelings," he said in his acceptance speech before about 1,000 people in an Oslo City Hall auditorium with huge murals adorning soaring marble walls.
Since his earliest days on the stump, Obama has relied on rhetoric that holds up lofty ideals but at the same time acknowledges politically pragmatic goals. In reaching out to the Muslim world, for instance, he has promoted human rights and justice but also focused tightly on common national interests.
Thursday's speech was a clear acknowledgment that although Obama favors negotiations and international cooperation, he is also a staunchly traditional American leader intent on guarding U.S. interests and prerogatives.
"I face the world as it is, and cannot stand idle in the face of threats to the American people," Obama said. "For make no mistake: Evil does exist in the world."
Obama is the fourth U.S. president to receive the prestigious award, but the first to do so while waging a war.
His speech Thursday won praise from many U.S. conservatives, especially for recognizing the existence of "evil" and acknowledging the futility of negotiating with groups such as Al Qaeda.
"He clearly understood that he had been given the prize prematurely, but he used it as an occasion to remind people . . . that there is evil in the world," said former House Speaker Newt Gingrich in a radio interview.
At the same time, his emphasis on reducing nuclear arsenals and adhering to principles of international law were lauded by liberals and staunch war critics.
"How proud we are to hear him speak with such eloquence about the values of our country, his responsibilities as commander in chief and America's role in the world," said House Speaker Nancy Pelosi (D-San Francisco).
Still, antiwar critics said his troop buildup clashed with the peace prize, an irony Obama addressed without delay in his speech.
"Perhaps the most profound issue surrounding my receipt of this prize is the fact that I am the commander in chief of a nation in the midst of two wars," Obama said. "I am responsible for the deployment of thousands of young Americans to battle in a distant land. Some will kill. Some will be killed."
As Obama ramps up the U.S. troop level in Afghanistan to about 100,000 next year, he is reducing the number in Iraq, with a goal of a complete withdrawal in 2011.
He said he agreed with King that "violence never brings permanent peace" and praised international institutions devoted to preserving peace without conflict.
But he added, "A nonviolent movement could not have halted Hitler's armies."
Obama referred to the theological and philosophical concept of a "just war" -- an armed conflict waged as a last resort, using proportional force and caution for the lives of civilians.
"I believe that force can be justified on humanitarian grounds," the president said, citing the need to stop genocide or civil war, such as in the Balkans.
Obama did not apply the "just war" tenet to Afghanistan, where U.S. forces have been accused of inflicting unnecessary civilian deaths and have overhauled combat procedures.
He also pointed to justifiable U.S. military action in the last century, saying American force was instrumental in winning two world wars, a reminder to Europeans that costly American effort helped bring years of stability on their continent.
"Whatever mistakes we have made, the plain fact is this: The United States of America has helped underwrite global security for more than six decades with the blood of our citizens and the strength of our arms," he said.
Obama also responded to critics at home who have charged that he doesn't do enough to press for human rights around the world.
"I know that engagement with repressive regimes lacks the satisfying purity of indignation," he said. "But I also know that sanctions without outreach -- condemnation without discussion -- can carry forward only a crippling status quo."
He advanced the idea of what he called a "just peace" that includes not only civil and political rights but economic security and opportunity.
Analysts said it was one of the most blunt Nobel lectures in memory, but the message appeared to be warmly received by Nobel committee members, who each greeted Obama with smiles afterward.