Ever since taking office, President Donald Trump has been itching to cancel the Obama administration’s nuclear deal with Iran.

In February, he tweeted that Iran “has been formally PUT ON NOTICE,” while also grousing about the “terrible deal” his predecessor made. The administration certified that Iran was complying with the deal on July 17, when it was legally required to review the deal, but all accounts from inside the White House suggest that Trump did so extremely reluctantly. This recertification only lasts 90 days, however, so Trump will need to renew it in October. And it seems like there’s a real chance the deal doesn’t survive that round of scrutiny.

“They are not in compliance with the agreement and they certainly are not in the spirit of the agreement in compliance,” Trump said in an August presser. “I think you’ll see some very strong things taking place if they don’t get themselves in compliance.”

All of this raises a pair of questions: Is Trump making a valid argument when he says Iran is breaking the deal? And if not, what’s his actual problems with the agreement?

The answer to the first question is pretty clearly no. The International Atomic Energy Agency, which is in charge of monitoring the deal, has repeatedly certified that Tehran is complying with the limits on its nuclear program. The Trump administration has yet to produce any evidence to the contrary.

It seems instead that Trump’s case against the deal is more political and strategic: His team believes that Iran is an enemy of the United States, one that frustrates US objectives in places like Iraq and Yemen, and that the nuclear deal hasn’t done much to solve the problem.

“Iran is an adversarial power that is working against the vital interests of the region. The deal doesn’t make Iran any better, so the deal doesn’t serve our interests,” James Jay Carafano, a foreign policy expert at the conservative Heritage Foundation who served on the Trump transition team, tells me.

There’s a core truth to this case: Iran’s behavior is extremely problematic in a whole host of ways, from testing ballistic missiles to funding violent militia groups around the Middle East.

There are a two big problems Trump’s argument, though. First, Iran’s support for terror and missile testing — while problematic — aren’t prohibited by the deal, so Tehran isn’t violating the pact by doing so.

Second, and perhaps more important, there’s little reason to believe that scrapping the Iran deal would help the US counter Iran in other areas. The US would have a hard time persuading partner nations to reimpose sanctions if the Trump administration quit the deal for no good reason, which would mean Iran wouldn’t suffer very much from an American pullout and thus would have no reason to stop its misbehavior. What’s more, it would be completely free to restart its nuclear program.

There is, in short, no good reason to believe that withdrawing from the deal would help solve Trump’s real problem with Iran.

“It’s just the worst of all possible worlds: You walk away from the deal but you’re not going to get the reimposition of sanctions,” Jeffrey Lewis, a nonproliferation expert at the Middlebury Institute of International Studies, says. “If this administration walks away from the Iran deal, my suspicion is that Iran will end up looking just like North Korea, right down to the thermonuclear-armed intercontinental ballistic missiles.”

What Trump gets right about Iran

When you hear the Trump administration talk about Iran, then, it doesn’t tend to focus very much on the threat from Tehran’s nuclear program. Instead, it tends to talk about Iran’s broader policies toward the Middle East.

Iran “is responsible for so much instability,” the president said in a May 2017 speech. “It is a government that speaks openly of mass murder, vowing the destruction of Israel, death to America, and ruin for many leaders and nations.”

You hear similar language from his deputies. Defense Secretary Jim Mattis, for example, has called Iran the world’s “primary state sponsor of terrorism.”

They’ve got a point. Iran has long viewed itself as being locked in competition with the US and its regional allies, particularly Saudi Arabia, and has centered its geopolitical strategy on undermining America’s allies by supporting their enemies.

Iran funds hardline Shia militias in Iraq that commit human rights abuses against the Sunni minority, helping fuel support for ISIS. It has played a vital role in propping up Bashar al-Assad’s regime in Syria, sending a large contingent of Iranian Revolutionary Guards (IRGC) fighters and troops from its Lebanese proxy militia Hezbollah. It funds and arms the Palestinian militant group Hamas. It has played a growing role in fueling the Yemeni civil war, sending arms and money to the Houthi militant group that toppled the country’s internationally recognized government.

Tehran has also tested ballistic missiles despite UN Security Council resolutions warning it against doing precisely that (these tests, it’s important to note, don’t violate the nuclear deal).

Carafano said that addressing this kind of behavior is one of Trump’s top two priorities for the Middle East (the other being dealing with ISIS and other jihadist groups). And it appears to dominate the way the administration thinks about the question of canceling the Iran deal.

On September 5, UN Ambassador Nikki Haley gave a speech on the nuclear deal that was easily the most sustained policy address on the subject from any top-level Trump official. Haley didn’t come right out and say that the US should withdraw from the deal, but basically laid out a case for why it would be justified in doing so.

The core of her argument listed the ways that Iran poses a strategic threat to the United States — and argued that the deal limits America’s policy options for dealing with that threat.

“Iran’s leaders want to use the nuclear deal to hold the world hostage to its bad behavior,” Haley said. “It is this unwillingness to challenge Iranian behavior, for fear of damaging the nuclear agreement, that gets to the heart of the threat the deal poses to our national security,”

That’s about the pithiest expression of the administration’s critique of the Iran deal as you could expect: Iran does bad things, the Iran deal limits our ability to punish them for it, so we need to get out.

What Trump gets wrong about the Iran deal

The problem is that many experts believe that canceling the deal wouldn’t necessarily persuade Iran to change its behavior. The key reason why is that nuclear deal with Iran is a very limited and specific agreement.

It ends a series of punishing international sanctions on Iran imposed prior to 2015 in exchange for Iran ending a large swath of nuclear-related activity and agreeing to a strict regimen of international inspections to ensure compliance. The punishment for Iranian cheating — like operating prohibited technology used to produce nuclear material — is the reimposition of sanctions.

What’s important is that the Trump administration has not been able to point to a single area in which Iran is in violation of the deal’s specific terms. There’s very little evidence to support Trump’s claims that Iran is violating the deal or its “spirit;” in fact, all publicly available evidence suggests they are not.

“Since implementation day in January 2016, Iran’s compliance with its obligations has been effectively verified by the International Atomic Energy Agency,” a statement published by the Arms Control Association and signed by 80 experts explains. “As of August, no international organization or national government has made any allegations of Iranian violations.”

The deal is, in other words working. It is successfully constraining Iran in one specific area in which it was misbehaving — its nuclear program — which also happens to be the only area the deal was designed to cover. The nuclear deal was never designed to stop Iran’s support for Assad or end its ballistic missile tests.

If the US were to withdraw from the Iran deal without being able to cite any clear evidence then experts believe it would probably have little to no support from the rest of the world — which sees the deal, correctly, as a nonproliferation agreement alone.

This is a huge problem for the White House. The pre-deal sanctions regime only had bite because European and Asian powers agreed to place sanctions on Iran. The US alone does little business with Iranian firms; without European and Asian buy-in, any new sanctions wouldn’t really hurt Iran. And key countries in those regions have been crystal clear that they are against canceling the deal.

“France doesn't support the reopening of the deal. It should be rigorously implemented as it is now,” Gérard Araud‏, the French Ambassador to the US, tweeted on September 13. “How many times should we repeat it?”

This is one key reason experts like Lewis are so vehemently against canceling the Iran deal. It would likely lead to Iran restarting its nuclear program without giving the US any major source of leverage on other problems.

“There’s no chance the Europeans will go along with that,” Lewis says.

What’s more, the deal already granted Iran economic concessions — including unfreezing billions of dollars’ worth of assets — that the US can’t just undo. This is why even some critics of the Iran deal believes simply canceling the deal is a bad idea; Iran got many of its benefits up front, while the benefits to the US require maintaining inspections for years.

“The clock is not so easily turned back,” Michael Singh, senior fellow at the center-right Washington Institute for Near East Policy, writes in a mid-September New York Times op-ed. “Any realistic Iran policy must take this as its starting point.”

Indeed, Secretary Mattis essentially said as much in his January confirmation hearing.

“I think it is an imperfect arms control agreement — it's not a friendship treaty,” Mattis said. “But when America gives her word, we have to live up to it and work with our allies.”

Finally, there’s no reason to believe the US can’t challenge Iran in places like Iraq while keeping the nuclear deal, and its vital limits on Iran’s nuclear program, in place.

America is, for example, currently participating in the Saudi war against the Houthi rebels in Yemen and, under Trump, literally bombed Iranian ally Bashar al-Assad in Syria. Taking a longer view, the US struck to a number of nuclear nonproliferation agreements with the Soviet Union — and yet still managed to wage an entire Cold War against it.

There’s a whole host of tactics, ranging from exposing covert IRGC operations to interdicting Iranian weapons shipments to its proxies, that could be employed to challenge Iranian misbehavior. A comprehensive report from the Center for Strategic and International Studies, released in March, lists many of these — and notes that they’re all compatible with staying in the Iran deal, which it believes should be maintained.

“Revoking the [Iran deal] would allow Iran to resume its nuclear activities without oversight provisions and would have very little punitive impact on the country otherwise,” the report notes.

That leads many experts from both parties to conclude that Trump’s argument for canceling the Iran deal — addressing Iran’s misbehavior — makes little sense. Some believe the true motivation may be a tad more political.

Trump has vocally attacked the Iran deal, like he has many pieces of President Obama’s legacy, and hates being forced to publicly certify that it’s working. Adhering to the deal is humiliating and feels like a betrayal of his campaign promises. It’s very likely that he hates being put in a position where he is forced either to accept Obama’s deal or face the reality that destroying it would do more harm than good.

“It makes him,” Lewis guesses, “feel like a cuck every 90 days.”