June 13, 2013

Stephen Hadley was national security adviser in the George W. Bush administration. Joseph Lieberman is a former independent Democratic senator from Connecticut. Jim Steinberg is a former deputy secretary of state in the Obama administration.

International reaction to the latest round of unsuccessful nuclear talks with Iran more than two months ago has been disconcertingly muted. Perhaps, after nearly a decade of stalled negotiations, the world has become numb to Iranian intransigence, a policy that is unlikely to change no matter who wins the country’s presidential election Friday.

But a sense of crisis is warranted by the April deadlock in Kazakhstan, and it should be a turning point in the U.S. approach to Iran.

While Iran has been stonewalling the international community at the negotiating table, its nuclear program has progressed — and is poised to make advances that call into question the sustainability of U.S. strategy.

These advances include introducing next-generation centrifuges that can enrich much larger quantities of uranium more quickly, significantly reducing the time that Tehran will need to produce a nuclear weapon. Iran is also making progress on a heavy-water reactor capable of producing plutonium, which could provide an alternate path to the bomb by the end of next year.

These developments reflect Iran’s broader success in fundamentally transforming its nuclear program over the past decade despite increasingly tough sanctions.

When the International Atomic Energy Agency issued its first report on Iran’s nuclear activities, in June 2003, Tehran had no working centrifuge facilities and no stockpiles of enriched uranium. Ten years later, it has almost 17,000 centrifuges at two compounds and more than six tons of uranium enriched to 5 percent purity; if further enriched, that could produce approximately five nuclear bombs.

Iran also has a growing stockpile of uranium enriched to 20 percent, which is significantly closer to weapons-grade. Some have suggested drawing reassurance from the fact that Iran has been shunting some of this stockpile into a form that is less proliferation-sensitive. It could, however, be converted back into centrifuge feedstock in a short period.

We have been strong supporters of a dual-track approach to Iran that has combined increasing pressure from sanctions and diplomatic isolation with persistent efforts at negotiations with Tehran. The Obama administration has been right to pursue this path over the past four years.

But given Iran’s accelerating nuclear advances and refusal to engage in meaningful negotiations, the time is fast approaching when diplomacy will be of little or no value or credibility. The United States urgently needs to take several steps that will significantly sharpen the choice faced by Iran’s leaders.

First, we believe the United States — with the other permanent members of the U.N. Security Council and Germany — should put forward a bold, comprehensive settlement offer that would be attractive to the Iranian people and viewed as more than fair by the international community. Should Iran reject this offer, the United States would then be in a strong position to rally the international community for significantly tougher measures against Tehran. Such measures should include intensified multilateral sanctions against Iran — ideally through a new U.N. Security Council resolution that could universalize the energy, insurance and financial sanctions that the United States and the European Union have adopted over the past two years. Washington should also step up its own targeted efforts, both unilaterally and with allies, to disrupt and set back Iran’s nuclear program.

In addition, the United States needs to strengthen its position and credibility across the Middle East to change the calculus of Iran’s leaders. The Obama administration’s recent reengagement on Arab-Israeli peace represents a valuable step, but others are needed — in particular, much more decisive action to hasten the end of the Assad regime in Syria.

Even more directly, the Obama administration should signal unequivocally that the United States is prepared to take military action against Iran absent a diplomatic breakthrough.

We are convinced that if diplomacy with Iran fails, President Obama is serious that all options, including the use of force, are on the table. Unfortunately, there are indications that the regime in Tehran continues to doubt the seriousness of U.S. intentions, which makes a peaceful resolution less likely.

To counter this, the administration should publicly announce that it has plans for military action against Iranian nuclear and missile facilities, conduct military exercises in the region in a systematic and sustained way consistent with those plans, deploy U.S. military forces to protect critical assets of our allies in the region and prepare to close down overseas Hezbollah cells and expose Iranian intelligence agents.

The administration should also begin consultations with our allies in Europe and the Middle East about the growing prospect that military action will be necessary as well as talks with Congress where, we believe, a strong bipartisan majority is ready to give the president the authority to take necessary action.

It is no longer possible to shrug off the ongoing diplomatic impasse with Tehran. The United States and the international community must approach this crisis with the clarity, determination and urgency it demands and deserves.