Uncomfortable Lessons: Reassessing Iran’s Missile Attack

Photo Credit: Ayman Henna / AFP

Nearly one month has passed since Iran attacked U.S. troops in Iraq with a barrage of ballistic missiles. As considerably more information has now come to light, a reassessment seems in order. Initially characterized as a symbolic act to be shrugged off, newer information shows the attacks were of greater consequence. The available evidence, for example, no longer supports earlier assessments that Iran made a special effort to avoid killing Americans. The attacks also show that Iranian ballistic missile forces, both in technology and operational competency, have the potential to cause major disruption to the United States and partner military operations in the Middle East. Finally, the attack reveals that Iran is tolerant of strategic risk and less deterred by the threat of U.S. military action. This new situation may require the United States to adjust its posture of forward-deployed forces in the region.

Intent to Kill

On January 8, Iran’s Islamic Revolutionary Guards Corp (IRGC) launched an estimated 15-22 short-range ballistic missiles against U.S. troops at two Iraqi bases, a reprisal for the U.S. killing of key IRGC leader Qassem Soleimani. While some of the missiles failed in flight, many found their targets with surprising precision.

The Trump administration initially characterized the attack as having caused “no harm” to Americans and inflicting only “minimal” damage to the Ain Al-Asad airbase, which houses around 1,500 U.S. troops. Leaks from the Pentagon, as well as independent analysis (including my own), drew the premature supposition that the lack of fatalities was due to a deliberate Iranian effort to avoid killing Americans, thereby controlling the risk of escalation. The fuller picture of what happened the morning of January 8, however, no longer supports this conclusion.  

First, we now know that harm did come to Americans. While no base personnel lost their lives, at least 64 U.S. service members have been evacuated and treated for concussions and traumatic brain injury (TBI). This number has steadily increased and may go higher still, as TBI symptoms do not always present themselves immediately.  

These injuries may stem from the fact that not all troops were safe in a bunker during the attack.  Some U.S. soldiers remained in exposed positions to defend the base against a possible ground assault, while others remained above to continue drone operations. These troops have recounted coming into dangerous proximity to impacting ballistic warheads.

Even those in bunkers were not completely safe and may have been vulnerable to shocks of the impact. The air raid shelters at Ain Al-Asad were fit only to withstand hits from small munitions such as rockets and mortars. A Katyusha rocket, the most common type seen on Middle East battlefields, carries between 10-20 pounds of high explosive. Fateh-313 ballistic missiles, by contrast, can carry upwards of 1,100 pounds of high explosive. It is unlikely that these shelters could have withstood a direct hit from a ballistic missile. Two U.S. officers, including the base commander of U.S. forces at Al-Asad, reported that the strikes caused the shelters’ doors to “bend like waves.”

It now also seems clear that Iran did not “aim to miss” or select structures unlikely to contain U.S. personnel. Facilities hit by warheads included sleeping quarters—not a building to target at 1:30 a.m. if one intends to avoid killing people. Other targets included aircraft hangers and similar support facilities. U.S. military bases, particularly those overseas, bustle with activity 24 hours a day. As such, no one targeting the base could have known with any certainty that any given structure would be unoccupied at any given time.   

The timing of the strikes has also raised speculation that Iran may have had lethal designs with its attacks. The missiles came in several waves separated in some cases by over an hour. This kind of volley staggering is reminiscent of artillery tactics in which an attacker tries to give a false impression that the bombardment has ended to coax the defenders out of their shelters only to resume the shelling with more deadly results. According to base commander Lt. Col Garland, “it was just enough time to make you feel safe. It was my opinion that it was intended to inflict casualties.”

Iran did warn the Iraqi government approximately 90 minutes before its first missile salvo. While this notification may indicate some desire to limit the loss of life, it could just as likely been motivated by Tehran’s desire to limit damage to its relations with Baghdad. There was also no guarantee that the Iraqis would have passed the information along.

Ultimately, it was the ample early warning enabled by the U.S. intelligence, surveillance, and reconnaissance complex, which came well before Iran’s warning to Baghdad, that did the most to keep U.S. troops safe. Considering firsthand accounts of the attack, however, luck also played a big part.

Disruption to Base Operations

Having an airbase paralyzed by missile attack is one of the most troubling scenarios for forward-based U.S. forces and Pentagon planners. A study by RAND, for example, assessed that an attack with 50 ballistic missiles could render a major U.S. airbase unusable to large aircraft for a week.

Until quite recently, conventional wisdom among many open-source missile analysts was that, while improving, the precision of Iran’s ballistic missiles remained too poor to cause this level of disruption to U.S. military operations. A 2019 study assessed that a conventional ballistic missile would require achieving around 50 meters circular error probable, a measurement of missile accuracy, to be reliable against small or hardened military targets. The attack on Ain Al-Asad illustrates that Iran’s ballistic missiles have crossed that threshold, giving Tehran the potential capability to handicap the effectiveness of U.S. forces in the region.

Firsthand accounts of the attack indeed depict a base largely locked down in survival mode. Base personnel went into shelters around 11:00 p.m. and did not emerge until around 4:00 a.m. the following day. Other troops took dispersed positions off base and in aircraft. Some soldiers remained above ground to protect the base against a possible ground attack, and a handful stayed in the unhardened containers to keep the base’s surveillance drones operating in the air.

The operators, however, were unable to maintain drone operations during the attack. One of the pilots told journalists that an Iranian warhead struck the sleeping quarters next to the operation rooms, forcing the pilots to retreat to the bunkers. The attack also damaged the fiber wires connecting the pilot station to the communications equipment, severing their link from the aircraft above.  

In the case of Al-Asad, it was fortunate the situation permitted the base to suspend most activity until the attack subsided. Had the base been engaged in a full-scale conflict with Iran, such suppression of operational tempo could have major ramifications for the course of a conflict.

Iran’s attacks demonstrate the danger that advances in adversary missile capabilities pose to U.S. forces. The United States should take action to reinforce the security and deterrent value of its forces by decreasing their vulnerability to air and missile attack. Forward U.S. bases require hardening against conventional missile attacks, including shelters designed to withstand a direct hit from ballistic missile-class reentry vehicles. As U.S. forces become more vulnerable to precision attacks from the air, passive defense measures like hardening, concealment, and camouflage need more emphasis.

The U.S. Army, moreover, needs additional air and missile defense battalions. The Army’s air and missile defense force is thinly spread and underfunded. It should, therefore, be no surprise that Ain Al-Asad lacked missile defenses. Had a unit been there, it could have reduced the risk of fatalities or possibly dissuaded Iran from attacking in the first place. 

Fraying Deterrence

Regardless of whether Iran wished to inflict or avoid casualties, its leadership must have understood the chance of U.S. fatalities was substantial and was willing to act anyway. The heightened state of Iranian air defenses, tragically evident by the downing of Ukraine International Airlines Flight 752, makes it clear that Iran believed a U.S. response was a real possibility. 

That Iran would risk killing U.S. military personnel means its leadership believed the benefits of the strike outweighed the likely blowback. This calculus may represent a shift in Iranian thinking. Until now, Iran has largely acted against U.S. allies and interests through proxies. When Iran has acted directly, such as its attack on Saudi oil facilities, it has done so covertly and initially denied responsibility. In this instance, the Iranians acted openly, hurling more than 17,000 pounds  of high explosives at U.S. troops. This new audacity suggests that U.S. deterrence in the region has eroded to a new low.

The uncomfortable truth is that this event has grave implications for the state of U.S. deterrence, and it brought the United States and Iran much closer to war than the administration would probably care to admit. While additional defenses for U.S. forces are necessary, they are insufficient to maintain peace. Reestablishing deterrence in the region will not happen overnight and will require steady, predictable leadership.

Almost no one in the United States, including President Trump, wants a war with Iran. Yet had Iran killed U.S. troops in its attack, the pressure on the president to escalate further might have been considerable. Both the United States and Iran have little to gain from war. In that sense, both sides are lucky that there were no fatalities. Should there be a next time, that luck may not hold.


Ian Williams is a fellow in the International Security Program and deputy director of the Missile Defense Project at the Center for Strategic and International Studies in Washington, D.C.

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