Use It Or Lose It - Houthis and Escalation

The US response to Houthi attacks has been muted. Iranian weakness may hold the reason why.

“Navies exist for the protection of commerce.” Alfred Thayer Mahan, The Influence of Sea Power Upon History

For over a month, Houthi attacks on shipping have done serious damage to the world economy. Through small-scale, sporadic attacks on container ships, shipping companies have been forced to divert around the Cape of Good Hope, losing valuable time and causing immense cascade disruption. Despite this, the American reaction has been surprisingly muted. There were not, for example, immediate retaliatory strikes against these modern pirates to neutralize them as a threat. This seems contradictory to America’s navy’s role in protecting sea lanes through which the global economy moves.

To explain US reluctance to decisively take action against the Houthi rebels in response to their attacks on shipping, we must turn to fear of escalation. Firstly, it is not from the Houthis that the US fears escalation, but from Iran. At present, Iran is not a nuclear-armed state. But it is nuclear weapons from which Iran derives its deterrent power. Iran has a form of conventional deterrence based on asymmetric warfare. Despite its dismal economic state and backward military, it nevertheless maintains an extensive network of proxy actors such as Hezbollah in Lebanon, Hamas in Gaza, various militias in Iraq, and the Houthis in Yemen. Collectively, it terms these the “Axis of Resistance.”

In response to perceived American aggression, Iran can use this network to attack US interests in the Middle East, forcing the US either to accept the losses inflicted or respond, which would further embroil itself in the region and force it to pay the attendant political price. Small scale attacks by Iranian proxies in Iraq on US bases have increased in frequency. The concern of the United States is that a strong attack on Iranian proxies would cause escalation. 

To escalate would be extraordinarily costly and risky for Iran. The US has numerous allies in the region with which to counter Iran's proxies, including Israel, Turkey, and Saudi Arabia. In addition, American air power is not politically costly to employ and can have devastating effects on the long-term viability of Iran’s proxies. Thus, unless the United States chooses to blunder into a ground war with Iran, there is an extremely asymmetrical ratio of suffering between the two countries if escalation occurs. 

The Costs of Escalation

With all that being said, why does the Biden administration fear escalation from Iran? Surely the Iranians understand how much they have to lose? Since the US has stronger conventional capabilities, it follows that retaliation should have a deterrent effect rather than an escalatory one. If small attacks from Iranian proxies are met with overwhelming force, they ought to understand cause and effect and refrain from provoking further strikes lest they become embroiled in a disastrous war. 

Perhaps, under normal circumstances, this logic would hold. The US has long held a policy of retaliation for the purpose of deterrence towards these Iranian proxies. Retaliatory strikes create a simple logic of deterrence: force is met with greater force, restraint with equal restraint. Instead, at present, there is a belief that Iran will escalate in the face of further strikes, even though its conventional capabilities are vastly inferior. What has changed?

That the Houthis have been on the whole spared this treatment can best be explained by the ongoing Israel-Hamas war. At the start of the war, the US took seriously the threat that Iran would move to aid Hamas, its proxy, by attacking Israel on other fronts. Iran was ultimately successfully deterred from doing so. Hezbollah in Lebanon appears to be taking a relatively passive approach, firing sporadically across the border while its Gazan allies are annihilated. At the same time, American pressure has so far been sufficient to prevent an Israeli preemptive strike on Hezbollah. While no other fronts have been actually opened, as the case of the Houthis demonstrates, Iranian proxies have increased their harassment of Western interests. Paradoxically, the quiet from the West and the Biden administration in particular is precisely because of the vulnerability of Iran. 

Aggression from Vulnerability

Iran views Israel as an American proxy, projecting its own method of relations. Thus, Israel’s efforts to destroy Hamas are framed as part of the larger proxy battle between the US and Iran. From this standpoint, in response to the provocation of the October 7th attacks, an Iranian proxy is being systematically eliminated. This threatens Iran’s credibility, and as such, the token attacks of the rest of its network serve the political purpose of demonstrating some degree of solidarity with Hamas. More importantly, however, is how Iran perceives the destruction of Hamas as demonstrative of US intentions. 

Destruction in the Gaza Strip

In this way, it is clear why the United States is strongly opposed to an Israeli attack on Hezbollah, a terrorist group that harbors a deep hatred for the US. An expansion of the war from merely destroying Hamas into destroying Hezbollah or the Houthi rebels would be viewed in Tehran as an attempt to destroy Iranian influence in the Middle East. This drives escalation out of desperation. The loss of one of Iran’s proxies may not be itself a problem, but if it stands by while one is destroyed, why would anyone believe it will do otherwise when the next is destroyed? Even if the US is immeasurably more powerful than Iran and a war with it would be cataclysmically painful, if the US is set on regime change in Iran, the regime would prefer a war to start now. The alternative would be to allow the US to systematically destroy Iran's allies before the war begins and be left in an inarguably worse position.

How States Lose Control

This logic will be familiar to those who have studied the outbreak of the First World War. While many of the belligerents did not especially desire a war between the power blocs, their creation meant that every crisis involved gambling with one. Alliance members found it necessary to stand by one another, practically taking the idea of a small-scale war off the table. If Germany did not stand by Austria-Hungary, it faced the prospect of a later war with no allies at all. Likewise, the French and British could not fail to intervene in a conflict between the German bloc and Russia (even had they not signed the Entente) for fear of losing the opportunity to fight a two-front war against the Germans. Thus, even if no party felt confident enough in its chances or was desirous of a war between blocs to start one deliberately, each state was willing to risk war rather than fail to support its alliance partners. 

In 1914, fear of disintegrating blocs drove the powers of Europe to war.

Thus, states can be tempted by this logic to “use it or lose it” and attack before their enemies can weaken it any further via salami-slicing tactics. This concept is also familiar in nuclear strategy and explains why conventional war between two nuclear powers is so dangerous: if one state is struck in a way that imperils their ability to detect or respond to an enemy nuclear attack—say by attacks on communications, command, or signal intelligence systems–it must use its nuclear weapons or risk losing them by being the victim of a first strike. 

Iran’s Fear of Preemption

On a much smaller scale, Iran’s obligation to defend its allies explains American restraint towards the Houthi attacks. Iran is obligated not because it has signed some document, but because failing to do so risks entering an existential war with a weaker hand. As such, the US wishes to signal to Iran that it does not have broader ambitions to destroy Iranian power or effect regime change. 

Iran, at the same time, does not desire escalation but must balance that desire against its interests in maintaining its credibility both as a supporter of Palestine and of its network of proxies. As such, its aim is to subject the United States and Israel to as much violence as is possible without causing a war it does not want. The recent escalation by the Houthis in targeting shipping is a particularly dangerous gambit for Iran. If America retaliates decisively, calling the bluff, Iran will have the choice between accepting another of its proxies being seriously harmed or choosing further escalation. 

From the DoD website page on Operation Prosperity Guardian

The former is the most likely, given the dramatic costs for Iran in the event of a more direct confrontation. However, the prospect of the latter, for now, has proven to be sufficient in limiting the American response to escorting vessels through Operation “Prosperity Guardian.” If this fails to restore safe passage through Suez, it is likely that the US will be willing to escalate to direct strikes on the Houthis to reduce their ability to conduct these attacks. 

Thus, the cautious approach that the Biden administration has taken is based on a perception of Iranian fear and the concern that Iran, in its weakness, might seek to “preempt the preemption” by attacking when it perceives its proxies being systematically eliminated. The United States has therefore chosen restraint, which is a costly signal to Iran of its limited ambitions. In this way, the success or failure of Operation Prosperity Guardian and whether there is a serious Iranian response to US strikes on the Houthis will be the metrics by which the success or failure of this cautious approach can be judged.