War and peace
US President Barack Obama walked into Oslo's City Hall to long applause. He smiled cautiously, knowing that in the world-wide audience there were sceptics. For many the Nobel Prize had come too soon, too early in his presidency. It was a prize for good intentions.
Mr Obama addressed those doubts in the first minutes of his lecture. He accepted that his getting the prize had caused controversy. "In part, this was because I am at the beginning and not the end of my labours," he said.
He went on to accept that compared to some of the giants of history who had received the award before - like Martin Luther King and Nelson Mandela - "my accomplishments are slight."
He also knew that for some there was a contradiction in accepting a peace prize when he has just ordered another 30,000 troops to deploy to Afghanistan. He told his audience that he was a commander-in-chief in the midst of war. In a speech that was about war and peace he defended the use of force. "I face the world as it is and cannot stand idle in the face of threats to the American people," he said. "For make no mistake, evil does exist in the world."
Mr Obama then marked out what he considers to be the major difference between his administration and that of President Bush. He insisted that America must follow international agreements.
"America cannot insist that others follow the rules of the road if we refuse to follow them ourselves," he said. He then reverted to a theme that I had heard often during his election campaign. "We lose ourselves when we compromise the very ideals that we fight to defend," he said.
Introducing Mr Obama, the chairman of the Nobel committee, Thorbjorn Jagland, had praised the new president's commitment to oppose torture and to close the detention camp at Guantanamo Bay. That has not happened yet. Today, here was a president re-affirming all the idealism of his campaign while tempering them with the reality of power.
Earlier in the day, he had said that if he was successful some of the criticism would subside but if he was not "all the praise in the world and the awards in the world won't disguise that fact". Outside the president's hotel were small groups of people demanding that Mr Obama earn his prize. For them, the test will be the Copenhagen summit next week and the pledges made by the United States. Others were demanding an end to the war in Afghanistan.
It was a sober, cautious president who insisted on the one hand that the "instruments of war have a role to play in preserving the peace" while saying that "war itself is never glorious and we must never trumpet it as such".