Where to go from here regarding an Iran nuclear deal

Diplomats from Iran, the United States and five other powers gathered in Vienna last week to try to revive President Barack Obama's 2015 deal limiting Tehran's nuclear activities.

It did not go well.

Iran's new hard-line government showed up with maximalist demands, insisting the U.S. lift all its economic sanctions before Tehran takes any steps toward curbing its uranium enrichment.

And the Iranians went further: They said they wanted to reopen draft agreements that their predecessors negotiated only six months ago.

Meanwhile, the U.N.'s nuclear watchdog agency announced that Iran has escalated uranium enrichment at an underground plant in violation of the 2015 deal.

Tehran's actions drew harsh responses not just from the U.S., but also from its European allies.

"Iran right now does not seem to be serious," U.S. Secretary of State Antony J. Blinken said Friday.

In undiplomatic terms, Iran shot itself in the foot: It shifted blame for any impasse from the U.S. to itself.

In doing so, it raised a larger, more ominous question: Does Ayatollah Ali Khamenei, Iran's supreme leader, want an agreement at all?

"The Iranians know that compromise will be necessary to make a deal," said Suzanne DiMaggio, a nuclear arms expert at the Carnegie Endowment for International Peace. "But it's unclear whether this new group of hard-liners is willing and able to get there."

A little history is in order.

Obama and the leaders of China, Russia, Britain, France and Germany negotiated the 2015 deal to prevent Iran from acquiring the ability to assemble a nuclear weapon. Iran says its nuclear program is peaceful, but it has enriched some uranium to a level that is mainly useful as a step toward a bomb.

Iran initially complied, closing nuclear facilities and limiting uranium enrichment. But the economic benefits fell short of expectations: Western banks and businesses didn't flood Tehran with investments.

Then, in 2018, President Donald Trump denounced the agreement as "the worst deal ever," walked away from it, and imposed crippling economic sanctions.

For more than a year, Iran continued to obey the pact's nuclear limits, hoping other countries would undo Trump's sanctions. But the sanctions never came off, and in 2019 Iran began enriching uranium beyond the limits.

Under the deal, Iran's "breakout time" — the period it would need to build a nuclear weapon — had lengthened to about a year, a delay U.S. military officials said would give them time to react.

After Trump withdrew from the agreement, Iran reduced its breakout time to roughly a month.

"The main mistake was the withdrawal from the agreement," former Defense Minister Moshe Yaalon said. "It gave [Iran] an excuse to go ahead."

Where to go from here?

One sensible approach for the U.S. and its allies would be a step-by-step process, with sanctions coming off gradually as Iran moves back toward compliance with its 2015 commitments. But Iran has rejected that.

If Iran continues to escalate uranium enrichment, the Biden administration and its allies may opt for what some diplomats call "Plan B" — new economic sanctions and tougher enforcement of existing ones.

That may look, at first glance, like a return to the strategy that failed under Trump — but it would be done in coordination with U.S. allies, more like the sanctions policy Obama pursued a decade ago. The new sanctions would be designed to nudge Iran toward practical concessions, not the wholesale surrender Trump imagined.

But a delay in timing may suit Biden, too. Republicans are likely to call any deal a sellout; the president probably doesn't want a debate over concessions to Iran right now. And by hanging tough, the Iranians are giving Biden an opportunity to look tough in return.

A deal will be maddeningly hard to get — just as hard as it was for Obama in 2015.

What makes it worth pursuing, despite the obstacles, is the alternative.

Without an agreement that constrains Iran from moving closer to possessing a nuclear weapon, Biden or his successor may face an unpalatable choice: Accept an Iran with the ability to assemble a nuclear weapon or go to war.

It's surely worth taking more time, offering more flexibility and enduring more rounds of unproductive talks to prevent that moment from arriving.