In the spring of his first year in office, President Obama began pushing an audacious goal — to use diplomacy to bring about what he called "a world without nuclear weapons."
Before long, his campaign sputtered. North Korea tested nuclear weapons, partly in an effort to provoke the United States. Relations with Russia worsened, rousing memories of the Cold War standoff and complicating a growing global drive to disarm. Nine countries still have nuclear weapons.
Those setbacks make this week's framework deal to limit Iran's nuclear activities crucial to Obama's nonproliferation agenda, administration officials say. If a final deal is reached, they believe it will vindicate Obama's argument that diplomacy can work even with seemingly intransigent negotiating partners.
But the prospect of a deal between Iran and six world powers, including the U.S., also illustrates the limits of Obama's aims. The agreement might hold off a nuclear arms race in the Middle East, but would not curb what the U.S. sees as Iran's military aggression in the violent region. Obama promoted it as a deal that would make the world safer. But on the nuclear front, the framework leaves unaddressed more existential threats to the U.S., including Russia and China.
"At the height of the mountain is the goal of a no-nuclear world," said former Sen. Richard G. Lugar of Indiana, a Republican who has worked for decades on destroying and securing weapons of mass destruction around the globe. "We may be at the bottom of the mountain right now."
Obama's pursuit of a nuclear-free planet has its roots in his short tenure in the Senate. As a member of the Foreign Relations Committee, he traveled with Lugar to Russia, Azerbaijan and Ukraine to inspect nuclear facilities, and he developed a deep interest in the idea of international diplomacy. Soon he was talking about initiating conversations with Iran, a deeply conservative Islamic nation with which the U.S. broke off formal ties after students took 52 Americans hostage in the U.S. Embassy in Tehran in 1979.
Obama's plan to negotiate with Iran ignited a fierce controversy during his 2008 campaign. Nonetheless, he embraced it as an issue central to his presidency, that the U.S. should withdraw from and avoid military conflict while engaging in multilateral and one-on-one negotiations even with world leaders hostile to the West.
In 2009, Obama made sweeping promises in a speech in Prague, proclaiming that the U.S. had a "moral responsibility" to lead the world toward a nuclear-free reality. He was trying to nudge U.S. policy back toward disarmament after the Bush administration withdrew the U.S. from a bedrock nuclear treaty with Russia, alarming opponents of nuclear weapons.
"The most important thing about the Prague speech was resetting the international frame, placing value once again on the idea of working toward disarmament," said Jon Wolfsthal, a longtime nuclear advisor to Obama and Vice President Joseph Biden who helped to shape Obama's nonproliferation agenda.
The address kicked off a year in which the president pushed several nonproliferation initiatives, capped off by signing the New START strategic arms reduction treaty with Russia. That fall, he was awarded the Nobel Peace Prize, with the committee citing his work on nuclear-arms reduction.
"When he said that we seek a world without nuclear weapons," Wolfsthal said, "he was resetting the way the U.S. was seen internationally."
The administration had hoped that New START would generate momentum to get nuclear materials out of other countries.
The treaty got caught up in so much political wrangling, though, that it finished with barely enough steam to be ratified, much less to produce further results. Meanwhile, the global movement toward nonproliferation faltered: North Korea's militarized nuclear program and the lack of safeguards protecting the fast-growing atomic arsenal in Pakistan emerged as major concerns for the administration.
Elsewhere, Libya drew international military intervention even though it gave up its nuclear weapons and tried to normalize relations with the West, noted Michaela Dodge, a nuclear weapons modernization and arms control policy analyst at the conservative Heritage Foundation.
"Since Prague, we see that we're nowhere closer to creating conditions for a nuclear-free world, and in many cases we're worse off," Dodge said. "The policy has not been successful."
In 2013, Obama delivered a speech in Berlin that many saw as dialing back the broad commitment to nonproliferation he made in the Czech Republic. The administration moved toward refurbishing warheads, rather than destroying them.
"The president simply has had to note the facts of life around the world," Lugar said.
Advisors to Obama see a deal with Iran as a long shot worth the effort because of a big potential payoff: reinforcing the growing global consensus toward nuclear disarmament that he trumpeted as a new president. It could also reinvigorate Obama's nonproliferation agenda.
The president spoke of the agreement this week as the best available option for keeping the Iranian nuclear threat at bay. In an address in the Rose Garden shortly after the framework was announced, he laid out two alternatives: more sanctions or bombing Iran's nuclear facilities. He moved to counter expected criticism by explaining why those options were unpalatable.
"When you hear the inevitable critics of the deal sound off, ask them a simple question: Do you really think that this verifiable deal, if fully implemented, backed by the world's major powers, is a worse option than the risk of another war in the Middle East?" he said. "Is it worse than doing what we've done for almost two decades, with Iran moving forward with its nuclear program and without robust inspections? I think the answer will be clear."
When it comes to nuclear-arms reduction, there are few blockbusters that Obama is likely to achieve, administration officials acknowledge. The June deadline for a final deal with Iran presents a moment for Obama to burnish his legacy on a major foreign-policy issue and to bring a renewed, if tempered, optimism to his long-held vision of nonproliferation.
The agreement, to essentially limit Iran's nuclear program for 10 years, could also buy the U.S. time to lengthen the arrangement, said Steven Pifer, a State Department and National Security Council official in the Clinton and George W. Bush administrations and now a nonproliferation expert at the Brookings Institution.
"It would be defusing a potentially big problem," he said.