In his September 23 speech to the United Nations, President Obama laid out his approach to foreign policy. "Those who used to chastise America for acting alone in the world cannot now stand by and wait for America to solve the world's problems alone," he said. "We have sought -- in word and deed -- a new era of engagement with the world."

What the president declared was a conditional end to American unilateralism. The condition? That other countries set aside their reflexive anti-Americanism and adopt a more cooperative relationship toward solving global problems. Obama drew some immediate, if surprising, responses. Venezuelan President Hugo Chavez, who called President Bush a "devil" when he addressed the U.N. three years ago, said this time, "It doesn't smell of sulfur here anymore; it's gone. It smells of hope." Libyan leader Muammar el-Qaddafi told the world body that he would be "happy and content if Obama can stay forever as president of America."

The real test is Iran -- not whether it becomes more co-operative with the United States but whether the U.S. can persuade other countries to cooperate in keeping pressure on Tehran to end its nuclear program. The signs are promising. Russian President Dmitry Medvedev accepted the inevitability of sanctions, telling Obama, "We believe we need to help Iran to take a right decision." Britain, China, France, Germany, Russia, and the U.S. have opened negotiations with Iran in Geneva, the first direct talks between the Washington and Tehran in 30 years.

The pieces of Obama's new foreign policy seem to be falling into place. His decision to revamp President Reagan's missile defense program was politically risky. Critics accused him of caving in to the Russians. But Obama is replacing "Star Wars" with a missile shield aimed at countering the more immediate threat from Iran. A diminished Iranian threat could enhance the prospects for progress in the new round of Middle East peace talks.

That was another issue where Obama shifted policy and took a political risk: He backed down from his demand that Israel freeze all settlement expansion, but then called for negotiations on a comprehensive peace agreement to begin quickly. Israel and the Palestinians had been playing for time by insisting upon a proper "context" for peace negotiations. George Mitchell, the president's Middle East envoy, cut that short, saying, "We do not believe in preconditions. We do not impose them, and we urge others not to impose preconditions."

The biggest breakthrough came when Iran was forced to acknowledge a secret uranium-enrichment facility, whose existence Western intelligence had long suspected. With Iran caught cheating, the United States had what it needed, leverage to organize an international coalition to confront Tehran. Other countries sounded tougher than the United States. British Prime Minister Gordon Brown said, "The international community has no choice today but to draw a line in the sand."

French President Nicolas Sarkozy said, "Everything must now be put on the table. Let us not allow the Iranian leaders to buy time while the centrifuges are turning. And if by December there is no significant change in policy on the part of the Iranian leaders, sanctions will have to be taken." The Russians joined in. A Kremlin statement said, "Iran's construction of a uranium-enrichment plant violates decisions of the United Nations Security Council," and Moscow called for an immediate investigation.

That's multilateralism. If tough sanctions are imposed on Iran, they will not be "made in America." Obama insists he is not renouncing his earlier policy of engagement with Tehran. "We have offered Iran a clear path toward greater international integration if it lives up to its obligations, and that offer stands," the president said. The United States can speak softly because others are carrying the big stick.

The biggest challenge that Obama faces is, of course, Afghanistan. That war started out as a multilateral effort in 2001. There are still 39,000 NATO troops in Afghanistan, along with 65,000 Americans. If the president agrees to dispatch as many as 45,000 more U.S. troops, as the military is reportedly requesting, the situation could turn into exactly what Obama says he does not want: an American war.

This article appeared in the Saturday, October 3, 2009 edition of National Journal.

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