One year later, the nuclear deal between Iran and the major powers is working. It has substantially restricted Iran's ability to produce fissile material, the key ingredient for a nuclear bomb, and in that way has made the world safer.
We now have a score sheet on Iran's compliance with its nuclear commitments from the International Atomic Energy Agency, which is responsible for monitoring Iran's nuclear activities, and from U.S. officials. Since the deal was reached last July, Iran has, as required, removed and placed in IAEA-monitored storage two-thirds of the 19,000 centrifuges it used for uranium enrichment at a facility at Natanz. It has ended all uranium enrichment, a process that can be used to produce nuclear bomb-grade fuel, and removed all nuclear material from its once-secret facility at Fordow. It has reduced its stockpile of enriched uranium from 12,000 kilograms, with a purity as high as 5 percent, to 300 kilograms, with a purity of no more than 3.67 percent and hence less usable as weapons fuel. The core of a heavy-water reactor at Arak has been filled with concrete.
The bottom line: If Iranian officials decided to produce enough fissile material for a nuclear weapon, it would take at least one year; without the deal, it would have taken just two or three months. That has won over some critics of the agreement, like Moshe Ya'alon, who was until recently defense minister of Israel. Last month, he effectively endorsed it and said Iran no longer presented "an existential threat to Israel."
Initially, critics warned that because the deal allowed Iran to continue enriching uranium at a low level for peaceful purposes, it would spur other countries to pursue nuclear weapons. But Robert Einhorn and Richard Nephew, nuclear experts who worked for the U.S. government, said in a new report that Iran's neighbors were unlikely to do that or to succeed if they did.
Iran, however, has yet to experience the full economic benefits it had expected from the deal, which has weakened reformers like President Hassan Rouhani. It gained access to about $50 billion in assets that were frozen overseas, opened new foreign bank accounts and doubled oil exports, to 2 billion barrels a day, but it has not had the level of foreign investment that Rouhani had promised. While international sanctions have been removed, most U.S. nuclear sanctions remain, like a ban on access to dollars, which has complicated other dealmaking and made risk-averse foreign banks nervous about doing business in Iran.
One of the few exceptions that allow Americans to export to Iran involves passenger aircraft. A deal last month for Boeing to sell 80 passenger planes worth $17.6 billion to Iran Air, the national airline, and lease it 29 others could make other foreign companies more confident about entering the market.
It's important that Iran benefit from meeting its commitments, but there can be no complacency about enforcing all the terms of the nuclear deal.
Iran is still subject to separate U.S. sanctions for its failure to halt its ballistic missile program and improve its human rights record, and for aiding terrorist groups.
There are clouds on the horizon that raise doubts about whether the nuclear deal can be sustained. Those include growing tensions between Shiite-majority Iran and Sunni-majority Saudi Arabia, concerns in Washington about Iran's destabilizing activities in the region, and elections in the United States this year and in Iran in 2017 that could strengthen the forces eager to upend the agreement.