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The master of self-inflicted wounds has done it again. This time, President Donald Trump is walking away from meaningful, verifiable limits on Iran’s bomb program. The constraints on Iran’s nuclear program embedded in the 2015 Joint Comprehensive Plan of Action weren’t good enough for those in Washington, Israel, and Saudi Arabia inclined toward regime change and “kinetic” options — otherwise known as military strikes.

Now Tehran could become free to act without constraints and on its own timetable, without inspectors on the ground.

A president who mocked the deal that the Obama administration negotiated alongside the permanent members of the Security Council and the European Union will now be challenged to do better. Diplomacy isn’t Trump’s strong suit; trashing Barack Obama’s accomplishments is. Nullification of the Iran nuclear deal suits those with no faith in diplomacy, raising the prospect of harsher strategies, beginning with sanctions. If sanctions and diplomacy both fail, military options become more likely.

Trump’s stated rationales for walking away from the deal are weak. One reason, he said is that “it didn’t bring calm, it didn’t bring peace, and it never will.” But this wasn’t a peace treaty. It was a deal to verifiably block Tehran’s pathways to the bomb.

Why it’s misguided to link nuclear monitoring to other issues

With that comment, Trump was invoking the concept of “linkage” — conditioning a nuclear deal on improved behavior by an adversary outside the deal’s scope. That’s been tried before, most notably by the Nixon administration. Nixon wanted to rein in Soviet ambitions in the Third World. The Kremlin never signed up to linkage, and Nixon didn’t walk away from the arms control agreements that he and Henry Kissinger struck with the Soviet Union.

So why sacrifice verifiable and meaningful constraints on Iran’s nuclear activities because of Iran’s “malign behavior” — the White House’s words — in Syria, Lebanon, Yemen, and elsewhere? A smarter strategy would be to push back against Iranian ambitions while maintaining verifiable constraints on Iranian nuclear activities. Why would Trump make this an either/or proposition?

Another ostensible rationale for pulling out of the Iranian nuclear deal is, according to the White House “fact sheet” on the decision, that it “did not include a strong enough mechanism for inspections and verification.” In fact, the Iran nuclear deal calls for 10-year, verifiable limits on Iranian research and development of enrichment technologies; 15-year verifiable constraints on enrichment; 20-year monitoring of centrifuge production, and permanent constraints on a plutonium pathway to bomb-making.

To be sure, every existing monitoring regime could be strengthened (especially if US diplomats were negotiating with themselves, as opposed to with the Iranians). But no nuclear nonproliferation, arms control, or reduction agreement to date has ever been this intrusive. It includes the presence of international inspection teams to supplement continuous monitoring by sensors at sensitive sites, reinforced by intelligence-gathering by satellites.

In response to the Trump administration’s withdrawal, Tehran could decide to curtail or remove foreign inspectors. So how will Trump’s walkout lead to tougher on-the-ground monitoring?

Iran’s past nuclear efforts aren’t a reason to drop the deal. They’re the reason for the deal.

Yet another argument Trump uses is that Iran negotiated in bad faith and on false premises. Specifically, Iran failed to come clean on its bomb-making activities prior to 2003 when, by the account of the US intelligence community, these activities ceased. Nothing that Israeli Prime Minister Benjamin Netanyahu presented in his show-and-tell last week suggested that the efforts did not cease in 2003.

In any event, supporters of the Iran nuclear deal didn’t presume or argue that Iran had clean hands or that the regime’s blanket denials of bomb-related activities were credible. Instead, the deal’s backers wanted verifiable constraints on Iran’s nuclear program precisely because Tehran didn’t have clean hands.

Trump says he is ready to negotiate new terms whenever Tehran is willing — terms that have longer timelines for nuclear restraints and that address Iran’s ballistic missile programs along with its aggressive activities in the Middle East. Don’t hold your breath: The Iranians have signaled they have no interest in rewarding Trump’s walkout, but they might be willing to deal with European capitals if they are willing to part company with Washington on sanctions.

So what does this suggest for the future?

The White House says its goal is “to put Iran and its regional proxies on notice.” But on notice for what, exactly? The reimposition of tough US sanctions, and most likely additional new sanctions too, for a start. But no other party to the Iran nuclear deal is currently on board with Trump’s decision.

Even if France, Britain, Germany, and the EU bend — a crucial question, at present — their decisions will have little bearing on Moscow’s choices. Beijing will weigh its opportunities against possible sanctions that it is well poised to withstand.

If the Trump administration’s goal is regime change in Iran, that goal has become harder to achieve. Regime change happens primarily from within. But Trump’s move undercuts the deal’s chief supporter in Iran, President Hassan Rouhani, and his backers. Meanwhile, those who held strong misgivings about the deal and engagement with the United States will be further empowered.

If diplomacy and sanctions fail to achieve the Trump administration’s objectives, what then? In this context, the key passage of the White House’s fact sheet is the following: “Today’s action sends a critical message: The United States no longer makes empty threats.” A whiff of grapeshot wafts in the air.

What new threats are next? Imposing regime change based on the prospect of Iranian economic collapse? This seems fanciful even if Trump can bring everyone on board with tougher sanctions.

Responding in kind or in greater measure to Iran’s military tactics outside its borders now seems a given. Trump’s Memorandum to Cabinet Secretaries on his decision states that US policy will be “to disrupt, degrade, or deny the Islamic Revolutionary Guards Corps and its surrogates access to the resources that sustain their destabilizing activities.”

Tellingly, this is the same phraseology used to characterize US military activities against al-Qaeda and “affiliated” outfits. When applied to Iran’s Revolutionary Guards Corps, this can mean an open-ended campaign involving far more direct US military involvement.

Greater pushback against Iran’s regional ambitions is, in my view, warranted. But sanctions backed up by a greater US military presence in the region won’t stop Iranian nuclear and ballistic missile activities. For this, military strikes would be needed — strikes that Netanyahu has long hoped for and would readily join in.

Opening this Pandora’s box would invite a host of unintended but predictable consequences. If diplomatic and economic coercion strategies fail, Trump has boxed himself into the binary choice of being judged to have engaged in hollow rhetoric or carrying out military strikes.

The reimposition of sanctions is unlikely to change Iranian behavior for the better. Walking away from the deal is more likely to result in worse Iranian behavior and a steady drumbeat for airstrikes.

Michael Krepon is the co-founder of the Stimson Center.

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