The Stunning Effectiveness of Houthi Harassment

For more than a month now, the Yemen-based, Iranian-backed Houthi rebels have disrupted ocean-going trade attempting to transit the Suez Canal, a critical chokepoint in the global economic system. Despite the U.S. Navy’s assurances of their protection, neither the world’s merchants nor the maritime insurance markets have been reassured. Ships continue to avoid the Red Sea, opting to take the long way around the Horn of Africa. The resulting increased time and cost of moving goods by sea between Asia, Europe, and the United States, as reflected in the spike in freight rates, has placed a strain upon a still not fully recovered global economy.  

Such a minor player on the world stage causing such tremendous derangement in the global economic system should be a source of great concern to the United States and its allies. The longer the Houthis maintain their pressure, the more the economic costs will compound. Inflation may not yet be tamed. Not only that, but an array of unfriendly regional powers—Russia, China, Iran, and North Korea—are sure to be watching closely for any cracks in America’s resolve to remain the leader of the free world. The Houthi success—for that is was it is—prompts major questions. Are the seas safe and open? What are the broader implications? Is U.S. deterrence failing?

The Economic Costs

Houthi activities pose a significant economic danger. The world is (or should be) familiar with how Covid 19, the Ever Given blockage in the Suez Canal, and the Russo-Ukrainian War have all created “supply chain disruptions”—a ubiquitous phrase as the entire nation has felt its impact on their daily lives. The Ever Given blockage, which only lasted a short six days, is still a major contributor to the post-pandemic surge in inflation that has not yet subsided.

Iranian and Houthi actions are putting a further strain on global trade. Major shipping companies are now diverting traffic away from the Red Sea for the “foreseeable future.” Commercial shipping activity in the region has decreased nearly 60 percent; for a region normally carrying over 30 percent of global trade, this is staggering. Short term rates for container shipping between Europe and Asia are climbing, some as high as 173 percent since December; the Drewry World Container Index shows an increase of 115 percent on average. Even though some commercial maritime traffic continues through the Red Sea, it is not enough to stabilize rising rates. The United States is already experiencing economic disruption as a result.

Beyond the obvious economic implications, the ongoing crisis in the Red Sea is a direct challenge to the status quo; it reveals the parlous state of America’s role in maintaining the international order. As the world’s principal naval power, America’s natural role is to protect both the global balance of power and also global commerce. Both activities require keen attention to sea power; the current vulnerable state of the international system is testament to America’s inattention to it. The Red Sea crisis is a lesson for sea power—one that both U.S. policymakers and the U.S. Navy should learn immediately. 

Sea Power

The Houthi rebels are teaching the world an object lesson in sea power: As one of us has written previously, “the United States must take commerce interdiction and protection seriously,” because global economic stability and prosperity are fundamentally tied to U.S. naval primacy. Though Americans often fail to realize it, their national survival and prosperity depend on access to maritime commerce. Nevertheless, the lack of a serious challenge to American naval supremacy appears to have bred complacency among both the Navy and the American people who fund its existence. The interruption of maritime transport in any form is not only a threat to global stability and security, but is a matter of national security and domestic economic—and ultimately political—stability.

This is why the seeming failure of the U.S. Navy’s strategy of "presence" to discourage Houthi harassment of international shipping is so alarming. The U.S. Navy mission of presence turns out to be little more than having ships in position to deter would-be threats. Deterrence, as a policy, is based on punishment; the threat of retaliation supposedly discourages an attack. That the Houthis continue their attacks despite the Navy’s repeated strikes is evidence that it is not “deterring” anything. Indeed, presence for its own sake provides all of the risks of attempting to achieve deterrence while offering no strategic impact. The Navy’s devotion to presence thus betrays a deeper plight: aimlessness. The Navy has arguably forgotten its core purpose—ensuring American access to maritime commerce—and so is failing to explain effectively its role to the American people.

The upshot of presence as a tautological mission is over-deployments, reduced readiness, and a reduction in the psychological impact of the presence of U.S. naval assets. Furthermore, as individual combatant commanders compete for ships in the name of deterring threats, but, as ship numbers are reduced, these commanders— and therefore the Navy—are forced to do more with less, which translates into simply doing less. The decades-long reduction in size of the U.S. Navy makes presence unworkable in addition to being ineffectual. 

Is this then a matter for American diplomacy? Unfortunately, many look to American diplomacy to resolve tensions, assuming that the desire for peace is a sufficient argument for its attainment. But American diplomacy requires credibility; waiting several months to respond to attacks on international shipping only betrays timidity. And it tempts further probing of American resolve. What exactly presence achieves is not self-evident—the situation in the Red Sea alone demonstrates that the deployment of American naval forces no longer means what it used to. 

A Lesson in 21^st Century Sea Control 

The Navy’s current presence mission is problematic for 21^st-century maritime operations. Missile technology has rapidly accelerated, becoming faster and more capable of reaching across ever-further distances. Maintaining sea control is a taller order than in previous ages. 

Confined to the oceans and seas, navies are vulnerable to missiles and threats from land. As technology continues to develop, those distances continue to lengthen. Presence for its own sake exposes naval vessels inside of the weapon engagement zone of modern threats, without necessarily exercising local control of the sea. Indeed, the Houthis have shown exactly how difficult it is to maintain command of the sea in the 21^st century. Their small, asymmetric blockade may not be inflicting exorbitant, acute damages to ships, but the simple threat of attack has disturbed one of the globe’s major maritime chokepoints. 

Further complicating the matter, the Houthis have utilized cheap drones and ballistic missiles in their efforts. The U.S. Navy has praised the efforts of the USS Carney for its actions in combatting Houthi attacks, but the asymmetric costs cannot be understated. The Carney and other American ships in the region have likely employed SM-2 missiles (at an average cost of $2 million) against improvised drones and missiles that are estimated to cost maybe $2,000 apiece. To put this in perspective, the U.S. Navy is effectively spending a cost differential upward of 1000:1. Nor does the U.S. Navy possess an unlimited supply of SM-2s, which take months if not years to build. Furthermore, the Houthis have shown that they do not even need to sink vessels in order to hold a waterway hostage.

Sea control has both a peacetime and a military element. Sea control—a temporary military condition—nonetheless assures access to the sea for organic and friendly maritime vessels while denying access to the sea to adversaries. In contested waters where sea control is assured by a dominant power, the free flow of commerce may still be assured. Because of the mere threat of attack, however, commercial ships are avoiding the Red Sea altogether. A few attacks have nearly created a sea denial campaign simply by the threat of attack.

The question remains: Are the seas safe and open? What are the broader implications? Is U.S. deterrence failing?

The Red Sea has effectively been shut off from commercial activity. Nearly 60 percent of commercial traffic through the Red Sea has stopped, and the Houthis are continuing their attacks despite U.S. efforts. The seas may largely be safe over a wider geographical space, but the economic instability resulting from the Houthis affects the whole system. The knock-on effects are certain to be painful: Indeed, it appears that U.S. leadership is unwilling or unable to understand that global economic security underpins American political stability. They seem even less willing to understand sea power. 

As revisionist nations attempt to challenge the status quo, the United States appears to be stuck between its fears and its imperatives. Rather than adjusting to the challenges ahead, the U.S. Navy continues to rely on presence as its preeminent strategy. The United States must reconsider a strategy that is designed to satisfy its core purpose, even if this may require significant bureaucratic overhaul in the way we manage ship deployments to combatant commanders. 

Allies and opponents alike will draw the necessary conclusions about American reliability if there is no shift in our behavior. In demanding a halt to attacks on shipping, the United States has thrown down the gauntlet, but the Houthis have continued their attacks. America and its allies have reacted to Houthi determination, but there is now a risk that continued harassment of international shipping will place America on an action-reaction treadmill, making clear the ineffectual nature of “proportional response” and the hollowness of American deterrence. 

The asymmetric costs imposed on the United States are simply unsustainable, especially as global supply chains remain tumultuous. This is not simply a maritime problem. American conduct in one part of the world carries tremendous consequences for American—and global—interests elsewhere. 

Matthew Suarez is a captain in the United States Marine Corps. His views expressed here are his own and do not reflect the policy, opinion, or position of the U.S. Marine Corps, U.S. Department of Defense, or any other organization.

Brandon M. Patterson is a historian and strategist.

Image: A screenshot from video released by the Houthi movement's television network Al Masirah. (Video hosted by the BBC)