Past U.S.-Iran Confrontations Hold Lessons for Current Crisis

As Iran’s military ripostes to America’s “maximum pressure” campaign threaten to spark a broader conflict, U.S. decisionmakers should bear in mind the lessons of prior military confrontations. On several occasions over the past three decades, Washington has grappled with similar challenges of escalation, coercion, and deterrence, including the naval convoy operations during the Iran-Iraq War, the lethal assistance that Tehran provided to Shia militant groups “resisting” the U.S. occupation of Iraq, and the competing pressure campaigns that preceded the 2015 nuclear deal.

GULF CONVOY OPERATIONS (1987-1988)

In response to Iranian small-boat attacks on neutral shipping during the latter phases of the Iran-Iraq War, the United States initiated Operation Earnest Will in July 1987 to escort reflagged Kuwaiti oil tankers in the Persian Gulf. With the start of operations, the Reagan administration warned Iran against attacking the convoys with Silkworm missiles as they transited the Strait of Hormuz. The administration assumed that the presence of the USS Kitty Hawk carrier group would deter Iranian countermoves.

Yet while the launch of convoy operations spurred the Iranians to dramatically reduce their small-boat attacks, they were quick to challenge the United States indirectly; during the very first convoy, the tanker Bridgeton struck a covertly sown mine. Due to the limited damage, lack of casualties, and a desire to avoid escalation, U.S. officials declined to respond.

Within months, however, Tehran ramped up both its small-boat attacks and its mining operations. In September 1987, U.S. forces caught the Iran Ajr laying mines in international waters; they scuttled the ship and detained the crew. The following month, regime forces launched two Silkworm missiles at a reflagged tanker in Kuwaiti waters, skirting the U.S. redline by conducting the attack somewhere besides the Strait of Hormuz. Perhaps to obscure their role, the attackers used captured Iraqi Silkworms from the occupied al-Faw Peninsula. The United States responded by destroying two Iranian oil platforms used to support attacks; Iran retaliated with a Silkworm strike against Kuwaiti oil terminals that instead hit a decoy barge.

After Washington adopted more assertive tactics, Iran launched another mining operation in February 1988. The destroyer USS Samuel B. Roberts struck a mine two months later, spurring the Navy to destroy two more oil platforms used to support Iranian operations. In response, Iranian naval forces attacked several U.S. warships, which led the U.S. military to launch Operation Praying Mantis. During this action, the Navy sank an Iranian missile boat, frigate, and small boat; it also damaged a second frigate and several small boats, which fought on despite facing long odds. This marked the end of Iran’s mining operations, and with the ground war turning against it, attacks on shipping declined sharply for the duration of the fighting.

In July 1988, during one of these increasingly rare surface actions, the USS Vincennes accidentally shot down an Iranian Airbus passenger jet, mistakenly believing it was a fighter jet. All 290 passengers perished, and Iran apparently believed it was an intentional act. The perception that the United States was entering the war on Iraq’s side helped convince Tehran to end the conflict.

In sum, Iran was not deterred by initial U.S. intervention, and American restraint only emboldened it. Tehran challenged the United States by indirect means (covertly sown minefields), circumvented U.S. redlines by using missiles against reflagged ships no longer under escort, and ramped up attacks on unescorted shipping that was not part of the reflagging operation. The regime did not pull back until its own costs became prohibitive. At the same time, U.S. intervention apparently deterred direct attacks on convoys, forced Iran to rely on less effective tactics, and eventually contributed to a diplomatic solution to the fighting—though a series of devastating Iraqi victories on land contributed to this outcome and distinguish these events from today’s crisis.

PROXY WARFARE AGAINST U.S. TROOPS IN IRAQ (2003-2011)

During the U.S. occupation of Iraq, Iran’s Islamic Revolutionary Guard Corps-Qods Force armed, trained, and financed Iraqi militias and insurgent groups that killed more than 600 U.S. troops. Tehran apparently hoped to tie down U.S. forces, dampen America’s appetite for further regional military adventures, and help its proxies eventually push the United States out of Iraq. With American forces ensconced next door and the stakes raised so high, Iran was willing to assume significant risk.

For its part, Washington sought to disrupt Tehran’s efforts while avoiding escalation, so it generally acted with restraint. The U.S. military regularly interdicted Iranian arms shipments, and after sending a warning note that went unheeded, it detained senior Qods Force operatives on several occasions: two in Baghdad (December 2006), five in Erbil (January 2007), and another in Sulaymaniyah (September 2007). A Hezbollah operative working for Iran was detained as well (July 2007). These detentions led Iran to seek direct talks with U.S. representatives in Baghdad (which were inconclusive) and caused the Qods Force to dramatically reduce its footprint in Iraq. The United States also privately threatened military ripostes to attacks by pro-Iran groups, including rocket strikes on the U.S. embassy in Baghdad in April 2008, and rocket strikes against several U.S. bases in June 2011. The latter attacks killed fifteen soldiers. In both cases, strikes ceased after stern U.S. warnings.

Overall, Washington’s efforts to constrain Iran’s support for Iraqi proxies produced only modest results. The detention of Qods Forces operatives compelled Tehran to change its modus operandi and provided a brief impetus for renewed diplomacy. Private threats of escalation twice caused Iran to stand down. But U.S. actions ultimately failed to halt Tehran’s support for attacks on American forces or limit the growth of its influence in Iraq. Moreover, Tehran made no effort to hide its role: for example, the arms it shipped to militant Shia groups often retained the manufacturer’s logos and data plates. The standoff provided by proxy cutouts was apparently more important to Iran than deniability; the regime correctly calculated that the United States would not respond militarily to proxy operations even when Iranian sponsorship was evident.

COMPETING PRESSURE CAMPAIGNS (2010-2012)

In light of Iran’s willingness to continue nuclear activities that violated a half dozen UN Security Council resolutions, the United States, Israel, and the European Union ratcheted up pressure in order to halt these activities through coercion or negotiations. Washington and Israel intensified their joint campaign of cyberattacks on the nuclear program, continuing them at least through 2010. Israel reportedly assassinated a number of Iranian nuclear scientists starting that same year, while also escalating its threats of preventive action against Iran’s nuclear infrastructure. The United States bolstered its forward military presence in the Gulf to deal with possible fallout from an Israeli strike and intensified its drone operations over Iran and its periphery. Perhaps most important, Washington and the EU imposed harsh sanctions on Iran’s Central Bank and oil sector in 2011-2012. Yet the threat of escalation deterred the United States from using military means to pressure Iran.

Iran responded in kind while eschewing steps that could spark a broader conflict. It launched cyberattacks on U.S. financial institutions (2012-2013) and oil giant Saudi Aramco (2012), plotted attacks on Israeli diplomats in retaliation for the assassination of scientists (2012), attempted to shoot down U.S. drones in the Gulf (2012-2013), and accelerated the nuclear program by increasing its number of operating centrifuges and its stockpiles of enriched uranium.

These dueling pressure campaigns became enmeshed with other covert campaigns, shadow wars, and overt conflicts that in many cases predated the nuclear crisis, including the Israel-Hezbollah conflict, the geopolitical rivalry between Saudi Arabia and Iran, and the Syria war. The involvement of so many actors operating independently or in concert only heightened the potential for crossover and inadvertent escalation.

Tensions eventually abated for a number of reasons. The United States and Israel curtailed their cyberattacks sometime after Iran discovered them in 2010; Israel stopped killing Iranian scientists and ceased threatening preventive action; and Washington reduced its Gulf presence in response to both the Israeli stand-down and sequestration in the U.S. military budget. More important, U.S.-EU sanctions had begun to bite, and nuclear negotiations were gaining momentum. While covert action and military pressure campaigns slowed the nuclear program, it was sanctions that eventually brought Iran to the negotiating table. Yet flaws in the 2015 nuclear agreement contributed to the Trump administration’s May 2018 decision to leave the deal, paving the way for today’s crisis.

IMPLICATIONS FOR THE CURRENT CRISIS

Several conclusions can be drawn from these past showdowns with Tehran:

Iran shows strategic constancy, tactical flexibility. Once the regime commits to a particular strategic direction, deflecting it from this course is often difficult. Tehran will frequently test or try to circumvent an adversary’s redlines, and while it may abandon a particular approach when faced with a firm response, it soon seeks alternative means of achieving its goals. It might relinquish those goals if they become too costly, but such a decision would depend on its assessment of Washington’s motivation, risk tolerance, and willingness to bear costs of its own. In countering the U.S. maximum pressure campaign, Iranian leaders may believe they are fighting for their survival, so their tolerance for risks and costs may exceed the Trump administration’s.

Iran favors indirection, ambiguity, measured actions, and patience. The Islamic Republic’s leaders have long realized that their anti-status quo policies will often bring them into conflict with the United States. To limit the potential for escalation, they have relied on indirect or covert means (e.g., mines), used proxies to provide standoff and deniability, limited themselves to tit-for-tat responses, and maintained a low operational tempo.

Some of Iran’s actions in the current crisis have been consistent with these precedents. In line with its tit-for-tat approach, it has mined oil tankers in response to renewed oil sanctions, and mined petrochemical tankers in response to sanctions on its largest petrochemical company. Throughout, it has tried to avoid loss of life, whether by planting limpet mines away from a ship’s crew spaces or targeting unmanned reconnaissance aircraft. This indicates that risk and escalation management remain priorities for Tehran.

In other ways, however, Iran has departed from precedent. In 2012-2013, for example, it fired at U.S. tactical drones, but last week it shot down a strategic drone, the RQ-4 Global Hawk. In addition, the scope and tempo of current operations may exceed prior campaigns when one considers its other recent actions in Gulf waters (attacks on tankers), in Iraq (proxy rocket fire on U.S. facilities), and in the Arabian Peninsula (Houthi drone attacks on a Saudi oil pipeline). Given increasingly onerous U.S. sanctions and Iran’s worsening economic situation, there is potential for even more dramatic departures from precedent.

Washington needs to balance prudence, restraint, and escalation. U.S. restraint has sometimes invited additional challenges by Iran, leading to the very outcome policymakers hoped to avoid. Other times, exaggerated fears of escalation have precluded U.S. officials from using all means at their disposal to achieve key policy objectives. Both dynamics are at work in the current crisis. The Trump administration’s maximum pressure campaign has leaned mainly on the economic and diplomatic levers, largely eschewing the military instrument. This could tempt Tehran to undertake even more aggressive actions. Likewise, the U.S. decision to undertake cyberattacks in response to the tanker and RQ-4 incidents underscored President Trump’s aversion to military action. Yet the administration’s ability to deter a strategically consequential Iranian cyber response may hinge on its perceived willingness to employ the conventional military means that it has thus far eschewed.

Michael Eisenstadt is the Kahn Fellow and director of the Military and Security Studies Program at The Washington Institute. He would like to acknowledge David Crist and Gregory Giles, whose work greatly informed this PolicyWatch.