Earlier this month, Yemen’s Houthi rebels sent a low-cost drone across the Mediterranean and into the air space above Tel Aviv, exploding it at very low altitude. The attack killed one person and wounded at least 10 others. This type of attack isn’t new — Hamas has used cheap rockets and drones for some time — but the damage in the Houthi attack on Tel Aviv shows the underbelly of asymmetric warfare. Specifically, it shows how cheap and sometimes makeshift drones can penetrate sophisticated and expensive defense systems.
Indeed, for nearly a year, the United States military has been locked in a protracted and costly war in the Red Sea and Gulf of Aden against a smaller, less advanced force. Since October 2023, Houthi rebels have disrupted commercial shipping lanes, leading to a monthslong conflict with American and other forces (including the United Kingdom and France, which have also deployed ships to the region for intercept missions) shooting down dozens of missiles and drones. American aircraft carriers, their supporting ships and air wings and other assets have expended million-dollar munitions at an almost daily rate, a cost that has now exceeded more than $1 billion, according to Navy Secretary Carlos Del Toro. And despite the Pentagon’s claims that efforts would “disrupt and degrade” Houthi capabilities, the low-intensity fight shows no signs of ending, while the cost of it keeps going up.
“If we’re shooting down a $50,000 one-way drone with a $3 million missile, that’s not a good cost equation,” Under Secretary of Defense for Acquisition and Sustainment William LaPlante said during testimony before a Senate subcommittee in May.
So why can’t the largest military, with the weight of the American defense industrial complex behind it, develop cheaper weapons?
Given both its size and its global scope, the American military has never been entirely limited to one form of strategy and munitions acquisition. However, the nature of ongoing conflicts drives what is prioritized. Two decades of the global war on terror left much of the strategy and resources going toward fighting on-the-ground insurgencies. Combat forces were up against improvised explosive devices (IEDs), the risk of sudden suicide attacks or ambushes, not swarms of drones or missiles. Even one of the most recent campaigns, such as the fight against the Islamic State group in Iraq and Syria, saw American forces providing extensive air support to Kurdish and Arab allies on the ground, but that was against a force with familiar capabilities. In recent years, the military has tried to rebuild its capabilities to combat rival powerful state actors, for what it sees as great power competitions with Russia and China. That meant scrapping projects built for past strategies, such as the littoral combat ship, a multibillion-dollar project, to build smaller ships meant for operations near shores. The ships were costly, broke down frequently and had troubled weapons platforms, leaving them the subject of criticism for poor performance. In either case, air defense has not been prioritized, and any work toward it has been focused on high-end interceptors aimed at countering modern missiles from what the military refers to as “peers,” meaning Russia or China.
“The wars fought after the Cold War were largely against those who did not possess threatening offensive airpower capabilities, and so it became less important to invest in this area,” James Patton Rogers, executive director of the Cornell Brooks Tech Policy Institute, told New Lines by email. “Instead, the IED was the weapon to beat.”
The outbreak of the war in Ukraine changed how militaries looked at global conflict. The war has been devastating for the Ukrainian people. It has also shown the world how modern technology and cheaply obtained tools can reshape conflict. Although the fighting is, in many ways, a straightforward fight between two large militaries, mixing infantry, armor and airpower for large offensives, the slow grind and stalemate has led to odd, almost anachronistic elements. While both armies fight from World War I-style trenches, they’re using cheap commercial drones modified to drop grenades on tanks. Moscow and Kyiv use modern military aerial drones made for war, but their soldiers are also creating and using cheaper, unconventional weapons while fighting on the front lines. And these makeshift weapons have been effective in inflicting casualties and providing reconnaissance, even being worked into combined-arms assaults. The do-it-yourself field weapons have also spurred both sides to develop effective and inexpensive ways to counter each other’s innovations. In some cases, this involves repurposing high-tech defenses but at a low cost, like the use of signal jammers meant to render drones useless. In other cases it’s a blunt approach, like simply shooting them out of the sky with any light artillery weapon. One Ukrainian unit rigged together six Kalashnikov rifles into a surface-to-air gun. The war has also highlighted two main challenges for other nations in a modern conflict: munitions supplies and drones. With neither side able to win early and decisively, the fighting has drained artillery ammunition stockpiles, both in the countries and in the nations supporting them. And the necessity-driven innovation behind cheap drone swarms or attacks shows how effective, and how quickly, these low-cost tactics can be against an advanced military.
In December 2023, more than a year into the war in Ukraine and two months into the fight in the Red Sea, LaPlante told an audience that the United States needs counter uncrewed aerial systems “at scale. We need lots of them, whatever they are — kinetic or non kinetic,” adding that “cost per unit matters.” For the kinetic option, that means new weapons — missiles or even a directed-energy weapon — that can intercept an enemy drone. The other option includes tools that indirectly disrupt or shut down an enemy drone, such as jammers. The recommendation is something he’s echoed since, but now in the summer of 2024, the military is still relying on the same, expensive air defense tools. Those include surface-to-air missiles and fighter jet-mounted weapons that can cost several million dollars per strike.
The U.S. Department of Defense has the highest military budget in the world. American forces are deployed across the globe, with force projection of carrier strike groups and bases small and large all over. It works closely with defense contractors, and military leaders are always looking ahead to future threats. So why do so many new weapons systems and technologies end up in the limbo the Pentagon calls the “Valley of Death”? That’s the Pentagon’s own phrase for the phase in development where new systems get stuck in the testing and refining stage seemingly indefinitely. Eventually they are replaced by something new as threats or tactics evolve, leaving these systems in testing, never widely fielded.
Thane Clare, a senior fellow at the Center for Strategic and Budgetary Assessments and a former Navy officer who served as commander for the guided-missile destroyer the USS Mustin, said that in many cases, ultimate authority is in the hands of the secretary of defense. The military is capable of quick innovation of new technology — Clare pointed to defense production in the 1950s and 1960s — but it depends on urgency from those at the top. It’s partly a mix of bureaucracy, appropriations and the reality of developing, testing and then fielding any new weapon or military system. With the scope of the different fields needed to move a system or munition from concept to adoption, it comes down to isolating a specific issue to solve and having one person fully responsible for the work.
Recently, the military has been dealing with an essentially outdated playbook, according to comments by LaPlante. He noted in February that the Pentagon’s budget for counterdrone efforts was for the most part created before the invasion of Ukraine. The Pentagon needs “more flexibility handling appropriations” in regard to changing threats.
U.S. Central Command (CENTCOM) remains tight-lipped about what specific munitions are used in the almost daily intercept missions against drones and missiles. However, the Navy has admitted that it has fired SM (Standard Missile)-2s, SM-6s and SM-3s to take down drones. Those missiles can range in cost from $2 million to as much as $27.9 million per piece, depending on what model and variant they are.
In October 2023, the Navy destroyer USS Carney shot down several Houthi-launched missiles and drones over the Red Sea in an hours-long engagement. It was the first time the U.S. intercepted a weapon fired by Yemen’s Houthi movement since the outbreak of the Gaza war. The Houthi rebels had pledged to target and block commercial shipping to and from Israel in the Red Sea and Gulf of Aden until the war ended. Since then, the U.S. and its partners have essentially engaged in a low-grade conflict with the Houthi movement, almost daily destroying from one to seven missiles, drones or radar sites. CENTCOM does not say how many munitions are used per strike or intercept, but a conservative look at costs puts those at more than $1 million per launch. Neither side shows any intent on backing down, and neither side shows any sign of running out of weapons or the ability to use them.
The Navy confirmed in July that the Eisenhower Carrier Strike Group, which had taken the lead in intercept roles for much of the Red Sea conflict, fired 155 Standard-series missiles as well as 135 Tomahawk cruise missiles (which cost approximately $2 million per unit). That’s more than half a billion dollars from when the Eisenhower Carrier Strike Group deployed to the region in October 2023 and left in June this year. Additionally, aircraft assigned to the strike group fired 420 air-to-surface missiles and 60 air-to-air missiles. The Navy did not break down what specifically were used, but the USS Dwight D. Eisenhower’s commander has previously pointed to an arsenal that includes AGM-114 air-to-surface (roughly $150,000 per unit), AIM-9X Sidewinder and AIM-120 air-to-air missiles.
The fight in Yemen is one of several battles the United States has been involved in throughout the region since the start of the war in Gaza. Iranian-aligned militant groups have been firing cheap one-way attack drones and missiles at American installations and bases in Iraq and Syria for months. Dozens of attacks have left U.S. troops wounded and suffering from traumatic brain injuries. In January, three U.S. Army reservists were killed in a drone attack at a remote outpost in Jordan. So far this summer, neither the U.S. nor Iran seem intent on escalating the situation into an outright conflict, leaving a network of ongoing but small-scale skirmishes around the Middle East.
If the risk posed by one group with access to cheap munitions is hard to stamp out, this spring highlighted how costly a large-scale attack by a nation-state could be. In April, Iran and its regional partners launched more than 300 drones, cruise and ballistic missiles toward Israel, in retaliation for an Israeli attack on an Iranian diplomatic site in Syria. Almost every single munition was shot down before it could reach Israel, with the majority intercepted by American forces. The U.S. scrambled fighter jets and used Patriot missile batteries and naval forces in the Mediterranean and Red Sea to take out the cheap inbound weapons. Some U.S. Air Force pilots even reached “ace” status — scoring five or more aerial “kills” — in the effort. It was an effective but costly operation, especially when considering the low cost to Iran. Again, the military is tight-lipped, but two Air Force squadrons shot down more than 80 drones that weekend, using AIM-9X Sidewinder air-to-air missiles (according to “kill markings” spotted on one squadron after the fact). At roughly $472,000 per missile, that is more than $35 million. And that was just one element of a wider military response, in just one weekend. By contrast, though difficult to ascertain exact figures, the Islamic Republic probably spent no more than $50 million on the attack in terms of pure munition costs.
There are several parallel projects at work in the Department of Defense. Some are focused on adaptability and multipurpose roles to get the most effectiveness out of them. The Army and Marines have ordered hundreds of “loitering munitions,” low-cost drones that can be loaded with a payload for high-accuracy “suicide drone” attacks or for surveillance. They are the “smart” version of the crude kamikaze one-way attack drones used by militants. And this year the Air Force has also announced a competition for cheaper cruise missiles, the first step in moving toward developing them.
One effort often compared to the search for lower-cost weapons is the ongoing push for greater artillery round manufacturing. The war in Ukraine, after the initial invasion was ground to a stalemate, devolved into brutal wars of attrition. While soldiers man trenches, artillery on both sides have dueled, reducing cities to rubble and leaving both sides burning through supplies of artillery rounds at a rate not seen since the Korean War, according to U.S. defense officials. After a few months of this, both armies are trying to produce more ammunition, with the U.S. and NATO allies — which supplied many of the 155mm rounds to Kyiv — ramping up production. That includes new production lines at factories meant to both help aid Ukraine and replenish stockpiles to maintain readiness. If that can be done relatively quickly, why can’t the U.S. rapidly produce a less-expensive munition?
That’s because artillery rounds are a “solved problem,” as Gregory Sanders, deputy director and fellow with the Defense-Industrial Initiatives Group at the Center for Strategic and International Studies, put it. It’s something that has been done. The challenge is in scaling up the rate of production, rather than creating something new.
“That doesn’t make it easy by any means,” Sanders said, “but this is the sort of problem the Pentagon and the Army, in particular, excels at.”
The military is generally good at identifying these threats and problems, Clare argued. But the “Valley of Death” persists because there has been no compelling urgency to push the military-industrial mechanisms toward action.
One solution that the U.S. military seems to be exploring in earnest is unconventional or, as some like to put it, science fiction-inspired programs. The military branches are currently developing and testing several different platforms for directed-energy weapons, or lasers. The Army, Navy and Air Force are all approaching different ways of fielding lasers. The Army, for instance, is already testing this in the field after it deployed the Palletized High Energy Laser (P-HEL) in an operational capacity. The P-HEL uses a 20-kilowatt focused beam — less than the 100-kilowatt laser the Army is testing on its Directed Energy Maneuver Short-Range Air Defense (M-SHORAD) vehicle but still powerful enough to burn through metal — to hit, burn through and destroy aerial targets such as drones. The Army later confirmed to Military.com that it had scored an anti-aircraft kill in the Middle East. What it destroyed has not been disclosed.
The appeal is obvious. While the initial development cost is high, a laser would be cheaper long term in the field. The U.S. has been studying the feasibility and applicability of directed-energy weapons for decades. Recent progress is promising, but the overall field is not new and the military is not yet widely using lasers on the battlefield. The Pentagon regularly addresses unsolved problems, but not quickly, Sanders said.
Maybe the U.S. military and its allies will widely adopt lasers. Or they’ll focus on using cheaper versions of an SM-2 or “loitering munitions,” such as the Coyote 2C, a small, ground-launched weapon that can be used partially as a reconnaissance drone itself or guided to intercept and destroy drones. Rogers noted that any new weapons system or tactic takes time to adapt to. That ranges from the time it takes to devise a new solution and the time it takes to manufacture and field that weapon, plus train operators on it. That happens “all while the enemy adapts their own strategies and technologies to evade the countermeasures fielded against them.”
Even if the military were able on short notice to find, test and rapidly produce cheaper weapons that could replace the expensive ones currently in service, actually fielding them is a whole other matter. For instance, even if new surface-to-air missiles were a one-to-one replacement for the weapons currently in use, the logistics of such an overhaul would take time. Clare said that in such a scenario, the military “can’t do magic” but instead would need to send those newer munitions out on the next force deployed, rather than what is currently in the field. The best measure until then would be to focus on opening up new production lines for what currently is in use to recapture supply until newer options are available.
While the Pentagon rushes to get more cost-effective tools to fight swarms of cheap, expendable munitions, there is the risk that newer tactics or weapons that the U.S. and its allies aren’t prepared for could suddenly emerge. The conflicts in Ukraine and the Middle East show how these technologies can evolve quickly, along with the tactics to fight them. Rogers noted that it’s likely that more autonomous characteristics will appear in antagonistic drones, larger swarms could be used to try to overwhelm air defenses and cheap weapons could become more precise. The U.S. and its allies can develop newer counters, but the tactics will keep evolving.
“Put simply, it is an age-old cat-and-mouse game of offense and defense, one that is constantly evolving and will not be solved overnight,” Rogers added.
Or, perhaps, it is more of a David and Goliath game. And David is destined to remain the more nimble and easily adaptable of the two.
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