The North Korean leader, Kim Jong Un, and President Donald Trump during the second U.S.–North Korea summit, in Vietnam, on February 27, 2019Leah Millis / Reuters

President Donald Trump faces two high-stakes nuclear problems with two rogue regimes. And in the pursuit of elusive grand bargains, he has relied heavily on one tool: “maximum pressure.”

But with neither North Korea nor Iran has the strategy yielded the ultimate nuclear deal so far.

With North Korea, Trump introduced an escalating series of sanctions and harsh tweets (remember “Rocket Man”?) that, after a tense few months of brinkmanship in the summer and fall of 2017, yielded quickly to maximum engagement. Trump and the North Korean leader, Kim Jong Un, have now held two summits, exchanged letters, and, in Trump’s words, “fell in love.” For Iran, the pressure phase looks nowhere near over; just this week, the United States dispatched an aircraft carrier and other military assets to the region and imposed yet another round of sanctions, as Trump has done repeatedly since pulling out of what he called the “disastrous” nuclear deal a year ago.

But Trump also said this week that he wished the Iranians would call him, and his administration has frequently held out the prospect of negotiations—perhaps a lot like the ones with Kim.

Trump hasn’t yet struck a nuclear deal with North Korea; he left the existing nuclear deal with Iran in pursuit of a better one, but that also doesn’t seem imminent. Sanctions and diplomacy take time to work, and in the meantime, sanctions arguably helped get Kim to the negotiating table, even if the negotiations now look like they’re floundering. In Iran’s case, though, whether the maximum-pressure campaign can even get that far is unclear.

For one thing, North Korean leaders had a long-standing goal of meeting one-on-one with an American president and getting the boost in international stature such a meeting would entail. For Iranian Supreme Leader Ayatollah Ali Khamenei, who heads a regime that holds “Death to America” as a mantra, meeting with an American president doesn’t help his legitimacy—it hurts it.

For another, the Iranians have the North Korean precedent to observe, and it won’t be lost on them that Kim’s willingness to engage hasn’t gotten him any sanctions relief so far. Finally, Iran may be deterred by American threats from harassing U.S. assets in its region—or it may start to see escalation as its only source of leverage.

On the U.S. side, there’s another key difference in how each campaign is playing out. Early in the North Korea pressure campaign, Trump was the one hurling hostile rhetoric, playing bad cop to then–Secretary of State Rex Tillerson’s good cop, who was trying to keep communication channels open. (Sample tweet pair: “I told Rex Tillerson, our wonderful Secretary of State, that he is wasting his time trying to negotiate with Little Rocket Man … Save your energy, Rex, we’ll do what has to be done!”) The dynamic has now flipped, with Secretary of State Mike Pompeo and National Security Adviser John Bolton driving a hard line on Iran. “I actually temper John, which is pretty amazing isn’t it?” Trump told reporters this week. “I mean, I have John Bolton and I have other people that are a little more dovish than him. And, ultimately, I make the decision.”

Trump, though, doesn’t get to decide how others react to his overtures. “Hostility to the United States isn’t as central to the identity of the North Korean regime as it is the Iranian regime,” Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace, told me. “In fact, one of the goals of Kim Jong Un is to have a normal relationship with the U.S. … whereas Iran’s supreme leader views normalization with the United States as a greater existential threat than continued hostility.” Khamenei was skeptical of negotiations with the United States when Iranian Foreign Minister Javad Zarif conducted them during Barack Obama’s administration; he will be even more so now that America has pulled out of the deal that resulted.

Some factions within Iran have advocated for engagement with the United States, and they won the argument during the Obama administration. But the fate of the nuclear deal has diminished their influence, Farzin Nadimi, an associate fellow at the Washington Institute for Near East Policy, told me. “The one [faction] that insists that it’s not the right time to start negotiations with the U.S. is the IRGC,” the Islamic Revolutionary Guard Corps, Iran’s main security organ, which the United States designated a terrorist organization in April.

In the meantime, the Trump administration is perfectly happy to keep sanctioning the Iranians, which officials say deprives the regime of money to fund terrorism across the region. The administration believes that the sanctions campaign is already successful; officials point to the fact that Iranian proxy groups such as Hezbollah have asked for donations and that Iranian-backed militia fighters are complaining of salary cuts. Pompeo emphasized again this week that the United States is seeking negotiations—having earlier laid out 12 demands, on everything from missile development to support for proxy groups to the nuclear issue.

But even if the Iranians never come to the table in the economic sense, “maximum pressure has been much more effective against Iran than North Korea,” Gary Samore, a professor at Brandeis University who once served as Obama’s White House coordinator for arms control and weapons of mass destruction, wrote in an email. This, he wrote, is “mainly because Iran is much more vulnerable to trade and financial sanctions than North Korea and because China is quietly doing enough to keep North Korea alive for fear that Kim [Jong] Un will do something desperate if economic pain [gets] too intense.”

In fact, even if Khamenei observed Trump’s Kim summitry and saw an opportunity to exploit the president’s love of pageantry, the fact that Trump walked away from the latest summit in Hanoi without offering sanctions relief highlights the risks of this path for Iran’s leadership. The Iranians have so far refused repeated overtures from the Trump administration, and in the wake of Hanoi, it’s not clear they could achieve quick concessions just by agreeing to meet with Trump.

Sadjadpour pointed out that Iran has very little leverage to get such concessions: “The United States amasses leverage with economic sanctions. Iran amasses leverage by restarting its nuclear activities and threatening regional chaos … Iran is just starting to amass leverage with escalation.”

Iran has kept observing the terms of the nuclear deal that the Trump administration left, though this week, Iranian President Hassan Rouhani threatened to pull back from some elements, including by increasing Iran’s stockpile of enriched uranium. Iran, unlike North Korea, possesses neither nuclear weapons nor intercontinental ballistic missiles. What it does have is many potential means to harass U.S. forces and assets in the Middle East. It could also try to pressure the other signatories to the Iran deal, all of whom are still party to it besides the United States, to side with it to preserve the deal. That in fact was the explicit aim of Rouhani’s threat this week, in which he gave European countries 60 days to help Iran economically—which would involve those countries facing U.S. sanctions—or else he would take more steps to dismantle the deal.

Yet even this was a fairly modest threat, and it came a full year after Trump withdrew from the nuclear deal, Suzanne Maloney, an Iran expert at the Brookings Institution, told me. If Iran’s intent is to split the Americans and the Europeans, the administration is betting that in the end, its allies won’t risk American sanctions to do business with a country they have little trade with anyway.

“I think what we see in all of this—and it’s reassuring in some respects; it creates other problems in others—is that Iran doesn’t have very many good options for managing the pressure that it’s been put under, and for retaliating in a way that actually advances its own interests,” Maloney said.

Which doesn’t mean negotiation is the solution it’ll seek. The tentative achievements of Trump’s negotiations with Kim, namely a lowering of tensions and a moratorium on nuclear and missile testing, have begun to unravel as Kim has resumed missile launches. Kim retains an arsenal of nuclear weapons and intercontinental ballistic missiles just as big as the one he had during the “fire and fury” days of two summers ago; the United States retains sanctions just as severe.

For Khamenei’s part, meanwhile, his economy is suffering, and the more Trump offers negotiations, the more the supreme leader himself appears to Iranians to be the obstacle to economic relief, Sadjadpour said. “Eighty million Iranians right now are being crushed under economic sanctions and massive mismanagement and corruption,” he said. “If they believe that talking to Donald Trump would ameliorate their day-to-day economic struggles, they’re not going to oppose that on principle.” The problem is that they’re not the ones who get to decide—the supreme leader does.

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