I would not recommend pulling out of the deal now — not when the International Atomic Energy Agency, whose inspectors monitor 27 separate sites, has certified that Iran is in compliance. Instead of nuking the nuclear deal, the United States should take other steps to check the growth of Iranian influence.It would send a terrible signal to other states that in the future might be interested in concluding an arms control treaty with the United States if Washington were to abrogate a treaty simply because of a change of administrations. Why would anyone trust Washington to keep its word ever again?Pulling out of the treaty now would isolate not Iran but the United States. If the Trump administration simply leaves the treaty, without re-imposing meaningful sanctions on Iran, the effect would be purely symbolic — and the symbolism would be of America standing alone. . . .Pulling out of the Iran deal without a reasonable provocation would only create international sympathy for Iran in spite of its appalling human-rights violations — and it would most likely leave the agreement in place anyway.
Without European support—and the reimposition of European sanctions in particular—it is unlikely the United States will be able to strike a better bargain on Iran’s nuclear program. Moreover, if the United States attempts to unilaterally reimpose secondary sanctions on foreign companies doing business with Iran, countries such as China and India will likely ignore or circumvent such measures. . . .There is little reason to believe that Trump’s combination of bluster, strategic impatience, international isolation, and diminished leverage would produce a better deal. In fact, there are many reasons to worry that the outcome will be a broken agreement, unnecessarily heightening the risk of military conflict or nuclear breakout
The Trump administration is already … imposing sanctions on companies linked to Iran’s ballistic missile program, its cyberattacks, and its terrorist-sponsoring Islamic Revolutionary Guard Corps (IRGC). There is much more to be done on the targeted sanctions front, including designating the IRGC a terrorist organization. But there are also important steps that Trump can take on the ground in Syria and Iraq. …In the case of Iraq, that would mean insisting that, once the Islamic State is defeated, the government disband the Popular Mobilization Forces, made up mostly of Iranian-backed militias, and create a Sunni civil guard to protect Sunni areas from Shiite aggression. That will not be easy to do, but the United States can gain important leverage if it does not bring its troops home after the Islamic State is defeated — if, that is, it does not repeat the mistake that former President Barack Obama made in 2011.