Last week, Iran and the United States briefly resumed indirect negotiations to resurrect the 2015 nuclear deal. Unlike the previous round of talks in Vienna, which broke down in March, this round was hosted by Qatar and did not include representatives from most other parties to the original accord: China, France, Germany, Russia, and the United Kingdom. Even though the talks ended without a breakthrough, the fact that Washington and Tehran agreed to this new format suggests a common interest in restoring the deal. U.S. President Joe Biden’s administration has a strong desire to put Iran’s nuclear program back in the box and to avoid choosing from an unappealing list of options for preventing Tehran from enriching uranium to near weapons grade and shrinking its “breakout” time to close to zero. For Iran, the strongest motivation is sanctions relief, which would permit it to sell oil and gain access to billions of dollars in frozen accounts. Such relief is especially important now, since Iran’s cash-strapped government has been forced to slash subsidies on dairy, eggs, and wheat, triggering public backlash and protests throughout the country.

To be sure, a common interest does not guarantee a renewed deal, as the absence of any progress in this latest round of talks indicates. Tehran has insisted that Washington remove the Islamic Revolutionary Guard Corps from its list of foreign terrorist organizations, something that Biden has publicly promised not to do. Still, I believe an agreement is likely at some point, even if the hesitancy of each side to appear to concede anything more may mean one could take time to materialize. It is, of course, also possible that the United States and Iran never overcome their differences. Or that Tehran, thinking Washington will concede under greater pressure, accelerates its nuclear program, accumulates multiple bombs’ worth of 60 percent enriched uranium, begins to enrich to 90 percent (weapons grade) and disperse its stockpiles, and denies access to international inspectors so that the world can’t see what it is doing.

Clearly, if there is no deal, or if Iran begins to ramp up its nuclear program as part of its negotiating strategy, the United States will need a better strategy for deterring Tehran. But even if the two sides reach an agreement, the Biden administration will need to improve its deterrence. That is because once the sanctions related to the 2015 accord have been lifted, Iran will have little need for a follow-on agreement, such as the “longer and stronger” deal the Biden administration previously touted. Moreover, key provisions of the 2015 deal will “sunset” in 2030, leaving Iran without limits on the size of its nuclear infrastructure, the number or quality of its centrifuges, or the level of its enrichment. In other words, come 2030, Iran may feel little reason not to advance toward a point where it is a turnkey away from a nuclear weapon capability. And resurrecting the deal would give Iran many more resources. As the Israelis, Saudis, and Emiratis are fond of pointing out, if the Iranians can flood their proxy militias in Iraq, Lebanon, Syria, and Yemen with weapons when they are under sanctions, imagine what they will be able to do when they are not.

To improve U.S. deterrence in the long run, Washington should publicly declare what Tehran will lose if it continues down its current path—and what it will gain from changing course. The aim must be to restore Iran’s fear of U.S. military action without putting the country in a corner with no diplomatic way out. On the one hand, Iran’s leaders must know that by pressing ahead they will risk losing their entire nuclear infrastructure, which has taken them several decades to develop. On the other, they should understand that the broad sanctions regime—with its practical limitations and chilling effect on doing business with Iran—will be lifted if they give up their nuclear weapons option and stop coercing their neighbors. 

NO ROOM FOR DOUBT

The Trump administration did not succeed in developing an effective deterrence strategy, and so far, neither has the Biden administration. President Donald Trump’s “maximum pressure” policy failed to deter Iranian attacks—whether direct or via proxies—against U.S. forces in Iraq and Syria, tankers in the Persian Gulf and the Gulf of Oman, and oil infrastructure in Saudi Arabia. Even the targeted killing of Qasem Soleimani, the leader of Iran’s Quds Force, did not halt proxy attacks against the United States, although it may have made Iran more cautious about killing Americans.

Biden’s approach has proved no more effective. He accepted Iran’s demand for indirect negotiations, permitted China to buy Iranian oil with no penalty, and took the Iran-backed Houthi militia in Yemen off the list of officially designated terrorist groups. Instead of moderating its behavior, however, Iran appears to have been emboldened. During the presidencies of Barack Obama and Trump, enriching uranium to 20 percent—the dividing line between low and high enrichment—was considered provocative. Now, Iran is not only enriching to 20 percent without consequence but has gone ahead and enriched to 60 percent, suggesting that it has little fear of a tough U.S. response. And so far, it has been right. (Israeli security officials told me that there was a debate within the Iranian regime over whether to enrich to 60 percent, with some officials arguing that it was too risky. Those who pushed to enrich no doubt feel vindicated and even more confident that the United States will not respond with force.)

To deter Iran from advancing its nuclear program and pursuing destructive regional polices, Washington will need an integrated strategy that draws on political, diplomatic, economic, intelligence, cyber, and military instruments. It will also need to spell out its posture, not just in private but in public as well. Washington must put Iran on notice—and condition the international community to expect—that it will respond with all appropriate means if it detects movement toward a nuclear weapon. As part of the 2015 deal, Iran pledged not to seek, acquire, or develop a nuclear weapon. Since the United States is publicly committed to preventing an Iranian nuclear bomb, it should hold Iran to its pledge whether or not the 2015 deal is restored. Instead of saying all options are on the table—a statement so commonplace that no one takes it seriously—the Biden administration should say that if Iran moves toward a weapon, it will jeopardize its entire nuclear infrastructure. Before announcing this change in posture publicly, the administration should privately explain its rationale to U.S. allies and line up their support.  When the United States is aligned with its allies on Iran, Grand Ayatollah Ali Khamenei and other Iranian leaders understand that it is better able to raise the costs to the Islamic Republic.  Moreover, keeping Iran politically isolated matters. Iranian leaders do not see their country as similar to North Korea. In their eyes, they are heirs to a great civilization, not a hermit kingdom.

The United States must aim to restore Iran’s fear of U.S. military action without putting the country in a corner.

Since Iranian leaders doubt that the United States will use force to prevent them from advancing their nuclear program, the Biden administration will need to take several steps to make its declaratory policy credible. First, it should instruct the U.S. Central Command to conduct exercises, both on its own and with allies in the Middle East, to rehearse air-to-ground attacks on hardened targets. Second, it should run exercises in which it refuels Israeli aircraft—something that would be necessary in any actual Israeli attack on Iran. What it should not do is what it did in May: deny that it refueled Israeli aircraft during a joint exercise simulating distant air-to-ground attacks. Washington needs to stoke Iranian fears of an attack, not give the country’s leaders reason to doubt it would ever act militarily against them.

Finally, to lend further credence to its declaratory policy, the United States should provide additional military assistance to Israel. As noted above, Israel needs better refueling capabilities to credibly and effectively threaten Iran’s hardened nuclear infrastructure. The Biden administration should therefore accelerate the delivery of the KC-46 tanker, an aerial refueling and transport aircraft that it has agreed to sell to Israel, but not before 2024 at the earliest. Agreeing to move up the timetable, perhaps on Biden’s visit to Israel on July 13 and 14, would signal to the Iranians that the United States is ready to enable an Israeli military option if necessary. Alternatively, it could send a similar signal by providing the Israelis with the Massive Ordnance Penetrator (MOP)—a 30,000-pound “mountain buster”—and leasing them a B-2 bomber to carry it. Israel currently lacks the ability to destroy Iran’s underground Fordow enrichment site, which is built inside a mountain, but an MOP and a B-2 would change that, underscoring that Washington is prepared to support Israeli strikes if necessary.

That is not to suggest that the United States should want Israel to act in its stead. Rather, it is to signal to Iran that Washington will act alone or with others to destroy Iran’s nuclear infrastructure if the country moves toward a nuclear weapon. Iran’s leaders must see any such move as dangerous to them; they must believe that the United States means what it says; and they must understand that it is preparing the ground for military action if Iran makes a diplomatic outcome impossible.  

SOMETHING TO FEAR

But Washington cannot focus solely on Iran’s nuclear program. It must also have a strategy for countering Tehran’s destabilizing regional behavior, preventing Iranian weapons from reaching Iranian proxies, and bolstering the defenses of U.S. allies and partners in the region—in particular against the drones, cruise missiles, and ballistic missiles of Iranian proxies. To that end, the U.S. Central Command could integrate the early warning, drone, cyber, and missile defenses of U.S. regional partners, although these partners would have to agree to do so.

At a time when many U.S. friends in the Middle East are worried that the United States is withdrawing from the region, defense integration is one way to reassure them and keep Washington embedded in the area. It has the benefit not just of sharing the burden of defense but also making the existing assets of individual countries in the region count for more. The United States would not need to provide additional defensive missiles to its partners if the missiles it has already provided could be pooled effectively. The sum of these weapons truly is greater than the individual parts. And to the credit of the Biden administration, it is already working to develop the security architecture for integrated air and missile defense in the Middle East.  

Finally, the United States must be prepared to respond more forcefully to attacks by Iranian proxies on U.S. forces in Iraq and Syria. Bases where U.S. forces are stationed have been targeted more than 40 times, but the United States has responded in a highly calibrated way only twice. Washington’s responses must be unexpected, and they must signal to Iranian leaders that, contrary to their assumptions, the United States is willing to use force against them. Maybe it is time to take a page from the Israeli playbook: hit Iranian—not proxy—targets in the middle of the night and don’t acknowledge it. The United States shouldn’t put Iran in a position where it must respond or lose face, but it should also make clear that it is no longer willing to tolerate these attacks. 

The goal of the United States’ declaratory strategy must be to establish deterrence. The more clearly Iranian leaders understand what they could lose, the more likely they will be to seek a diplomatic alternative. Of course, the United States will also have to make clear what Iran stands to gain from such an alternative. That could be far greater sanctions relief if Tehran agrees to a longer and stronger deal. A “more for more” agreement of this kind might be possible—but only if Iranian leaders are genuinely afraid of what they could lose without one. Ironically, it seems, restoring Iran’s fear of the United States may be the only way to avoid a war, limit Iranian threats in the region, and produce an acceptable diplomatic outcome on the character of the Iranian nuclear program.

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  • DENNIS ROSS is Counselor at the Washington Institute for Near East Policy and a former U.S. envoy to the Middle East who served in senior national security positions in the Reagan, George H. W. Bush, Clinton, and Obama administrations.
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