In the rose garden last Friday, Barack Obama, with a deep sense of humility and in the name of all mankind, reluctantly accepted the Nobel Peace Prize committee's decision proclaiming him president of planet Earth. He will be sworn in at a glittering ceremony in Oslo in December. In the meantime, Obama has decided to retain the title and the powers of president of the United States, commander in chief of land, sea, and air forces, and team captain of pickup games behind the South Portico. (Click here to follow Howard Fineman)

OK, I'm joking. Obama isn't going to be sworn in as planetary president. But it doesn't matter; in his mind, he already is. From the time he announced his candidacy, his appeal—and his sense of himself—has been global. After years of war and fear, he would be what George W. Bush was not: a man who thought of the whole world first and viewed it as one multicultural family.

Obama was the first presidential candidate to campaign from the outside in. He traveled to Africa to emphasize his Third World roots and then to Berlin, where he appeared at a delirious rally designed to impress the voters back home. It worked, and Obama took that global outlook with him into the Oval Office. For one of his first major speeches, he flew to Cairo, offering himself as a human bridge between the West and Islam in an event that had the aura of a Second Inaugural Address, this one aimed at the whole world. In New York City late last month, he became the first U.S. president to preside over a session of the U.N. Security Council.

In office for a mere nine months, Obama is now a full-blown "ism." And Obamaism—the idea that there must be shared global responsibility for virtually every problem we face—makes some obvious sense. Most of America's problems are indeed global: terrorism (though the president doesn't like to use that word anymore); rampant, job-killing capital flows; climate change; nuclear proliferation; the digital networking revolution. The Bush world view, in which we were a gated community, won't work. We cannot revive our economy, for example, without the coordination that world leaders talked about at the G20 in Pittsburgh. In that sense, the only thing the Nobel committee did by offering Obama the peace prize—and the only thing he did by accepting it—was to dramatize this soothing message.

But the president had better be careful. For one, what the world wants is not necessarily what America needs, or what the voters care about. Most of the world wants us to get out of Iraq and Afghanistan right now. Most of the world would like to see the dollar lose its role as the reserve currency. Many, many citizens of the world think that Hugo Chávez is a cool dude and that Iran has every right to buy uranium centrifuges and stash them underground. Obama might want to recall the cautionary tale of another president, Woodrow Wilson. He won the Nobel Peace Prize in 1919 for his leading role in founding the League of Nations—a naive, toothless enterprise that most historians now view as a tragic wellspring of World War II. And nothing the Nobel committee can offer him in Oslo is going to help him reduce the unemployment rate here in America, the biggest political threat that he and his party now face.

The bigger risk for Obama is personal. No one in recent decades has come into office with such high—perhaps dangerously high—expectations. Most of them are as yet unfulfilled. Now they are higher, even though the prize itself is regarded by some as too political to be taken seriously. If Obama were real estate, he'd be the most highly leveraged condo in the world, a one-man in--vest-ment bubble in Florida. Journalist Mickey Kaus suggested that the president decline the award pending some actual accomplishments in world affairs. Shrewd advice, but Obama did not take it.

To be sure, he tried to be humble in the Rose Garden. He allowed as how he did not feel he deserved the award for anything he had personally done—yet. Instead, he was accepting the award as a "call to action" for a "new-era engagement, an affirmation of American leadership on behalf of aspirations held by people in all nations."

Still, he wanted to reassure us that, against all the odds, he remains a regular, grounded fellow. He cited as evidence a conversation that he had had that very morning with his daughters about more important news: the birthday of Bo, the family dog. Bo has not won any prizes yet, but give him time. He is an Obama.

Howard Fineman is also the author of The Thirteen American Arguments: Enduring Debates That Define and Inspire Our Country .

© 2009