The Pyongyang-Tehran Axis

Defying precedent and conventional wisdom, President Trump says he’ll meet in May with North Korean dictator Kim Jong Un. Mr. Trump wants a sustainable deal that leads to North Korean denuclearization. The president’s critics scoff, and even his supporters are rightly skeptical. But Mr. Trump has conditions: His policy of maximum sanctions pressure will remain in place, Pyongyang must commit to the goal of denuclearization upfront, and it must refrain from missile or nuclear tests during talks. That may give him some leverage.

But if there’s one thing that would help Mr. Trump to succeed, it’s fixing the fatally flawed nuclear deal with Iran. The Iran-North Korea axis dates back more than 30 years. The two regimes have exchanged nuclear expertise, cooperated widely on missile technologies, and run similar playbooks against Western negotiators. The fear: Tehran is using Pyongyang for work no longer permitted under the 2015 nuclear deal while perfecting North Korean-derived missile delivery systems back home.

Iran and North Korea both began their pursuit by acquiring designs and materials from Pakistan’s infamous A.Q. Khan proliferation network. Reports of more extensive cooperation haven’t been confirmed: Iran reportedly sent its nuclear chief, Mohsen Fakhrizadeh, to a North Korean nuclear test in 2013. Last summer North Korea’s second-highest-ranking official reportedly visited Iran for 10 days. In early 2015, Defense Secretary Ash Carter said Pyongyang and Tehran could be cooperating to develop a nuclear weapon.

Missile cooperation is extensive. Iran’s Shahab-3 nuclear-capable ballistic missile, whose 800-mile range means it can hit Israel, is based on North Korea’s Nodong missile. The 1,200-mile-range Khorramshahr missile, which Iran showed off last year, was derived from North Korea’s BM-25

For years Iran watched Pyongyang play the Clinton, Bush and Obama administrations to advance its nuclear and missile programs. The Kim regime demonstrated how a relatively weak country could persuade the U.S. to yield on major concessions along a patient pathway to nuclear weapons and intercontinental ballistic missiles.

The Islamic Republic followed North Korea’s lead when it negotiated the enrichment of uranium and potential reprocessing of plutonium on its own soil, crossing what for years had been an international red line. In exchange for short-lived restrictions on its nuclear program, missiles and conventional arms, Tehran will soon have industrial-size capabilities to enrich uranium and possibly reprocess plutonium for atomic weapons, nuclear-capable missiles, and hundreds of billions of dollars in sanctions relief.

Mr. Trump appears determined to regain American leverage. On Jan. 12, he declared that he would reinstate the most powerful economic sanctions against Iran by May 12 unless Europe agrees to join the U.S. in fixing the Joint Comprehensive Plan of Action. His demands: Eliminate the deal’s sunset provisions, constrain Iran’s nuclear-capable missile program, and demand intrusive inspections of Iranian military sites. All of these conditions would be tied to a snap-back of powerful U.S. and European Union sanctions if Iran was found in breach.

To date the Europeans have refused to budge, especially on the sunset provisions, perhaps not believing Mr. Trump will leave the deal. They are adamant that nothing must be done to jeopardize the JCPOA, which they see as an important foreign-policy accomplishment—not to mention a lucrative one, with billions of dollars of potential Iranian business for their companies.

If Mr. Trump caves in to European pressure on the sunset provisions, the agreement will grant Iran a legitimate nuclear program with weapons capability within a decade. In that case, the president will be hard-pressed to get North Korea to agree to permanent denuclearization. If he agrees to let Iran keep testing nuclear-capable missiles that threaten Bahrain, Saudi Arabia, the United Arab Emirates or Israel, North Korea will expect the right to test nuclear-capable missiles to hit South Korea, Japan and Guam. If he buckles on an Iranian nuclear breakout time of less than one year or on the development of advanced centrifuges that enable an easier clandestine nuclear sneak out, he will signal to Pyongyang that it, too, can withstand American pressure. Then Pyongyang can resume its march to nuclear-tipped missiles that hold America and its allies hostage.

Former Obama-administration officials warn that if Mr. Trump abandons their Iran nuclear deal, North Korea will view the U.S. as an untrustworthy partner. The opposite is true. The North Korean dictator wants to talk because the Trump administration’s campaign of maximum economic sanctions pressure is working.

But if the president agrees to a fictional fix to the JCPOA, or if he responds to a stalemate by backing down from the threat to reimpose maximum economic sanctions, North Korea will see Mr. Trump as a paper tiger. Conversely, if North Korea sees that Iran is held to tough nuclear and missile standards, backed by the credible threat of crippling sanctions, Mr. Trump will be better positioned to make it clear to Pyongyang that he means business.

The path to a denuclearized Korean Peninsula thus runs through Tehran. If Mr. Trump fixes the fatal flaws of the Iran deal, or even if he scraps it because the Europeans balk, his high-stakes North Korean gamble may yet succeed. Even if it doesn’t, he’ll have stopped Iran from following North Korea’s path to nuclear weapons and the missiles to deliver them.

Mark Dubowitz is the chief executive officer of the Foundation for Defense of Democracies. Follow Mark on Twitter @mdubowitz.

Richard Goldberg is a senior adviser at the Foundation for Defense of Democracies. Follow him on Twitter @rich_goldberg.

Follow the Foundation for Defense of Democracies on Twitter @FDD. FDD is a Washington-based nonpartisan research institute focusing on national security and foreign policy.