Russia and Ukraine are fighting the kind of drone war the US military has been worrying about, and it's scrambling to prepare for a future that's already here

• The scale of the drone war in Ukraine is one of the most striking features of the conflict.
• For the US military, widespread drone use isn't a surprise, but it does present new challenges.
• The Pentagon has several efforts underway to strengthen its drone defenses quickly.

The drones clouding the skies over Ukraine have been one of the most visible and innovative aspects of the 18-month conflict. A range of drones, from jury-rigged commercial models to purpose-built military aircraft, are now being used for a broad set of missions.

Their proliferation has made it harder to move and hide on the battlefield, and the footage they record often spreads widely, providing an unprecedented view of a modern war. For US military leaders who watched drones appear in the Middle East, their use in Ukraine isn't a surprise, but it does confirm the arrival of a new aerial threat that will challenge US troops' ability to fight and survive in future conflicts.

"What has been intriguing is it feels like for probably the last decade or so, there has been this sort of vision of you get a bunch of low-cost drones that will swarm and operate on the battlefield," Mara Karlin, who is performing the duties of the deputy undersecretary of defense for policy, said at a Defense Writers Group event in early August.

That vision wasn't realized until until late 2020, when drones featured prominently in fighting between Armenia and Azerbaijan. "I think folks' eyes kind of opened up and said, 'Oh, wow, like that's what this might look like,'" Karlin told reporters.

That brief war as "the first laboratory to start to watch how that might have an impact on a conflict in terms of the way the platforms were being used," Karlin said. "Obviously, now we have seen that a whole lot, and that's really, really notable."

'I never had to look up'

The US military has used unmanned aircraft for nearly a century and has deployed them in combat since World War II, including for surveillance and strikes during the wars in Iraq and Afghanistan. Only recently have US troops come under attack from enemy drones — not the large, sophisticated unmanned aircraft but civilian models repurposed for attacks.

"I experienced my first air attack by a drone as a US forces member near Mosul in 2016," Stephen Townsend, the US Army general in charge of US Africa Command from July 2019 until August 2022, said at a Defense Writers Group event prior to his retirement.

"ISIS figured out how to arm their drones and attack us either with 'kamikaze' explosive-laden drones or drones that dropped" modified munitions, Townsend said. "They got pretty sophisticated with that, and we had to learn how to deal with that threat in 2016."

ISIS was launching dozens of drone attacks a month in northern Iraq and Syria by 2017. US troops and their Iraqi partners adapted with new tactics and new technology, but US troops in northeastern Syria were still facing attacks from modified drones in early 2020, which Gen. Frank McKenzie, the top US commander in the region at the time, said were likely carried out by the remnants of ISIS.

The proliferation of modified drones and widespread development of larger unmanned aerial vehicles was a new challenge for US ground troops, who had not been seriously challenged by aerial attacks since the Korean War.

"I've been in the Army for 38 years, and in my entire time in the Army — on battlefields in Iraq and Afghanistan [and] Syria — I never had to look up," Richard Clarke, who led US Special Operations Command from March 2019 until his retirement in August 2022, said last year at the Aspen Security Conference.

"I never had to look up because the US always maintained air superiority and our forces were protected," Clarke said. "Now, with everything from quadcopters that are very small up to very large unmanned aerial vehicles, we won't always have that luxury."

The presumption of air superiority "fed into the secondary problem of the counter-UAS capability not being where it needs to be, and now everybody's scrambling there," Tom Karako, director of the Missile Defense Project at the Center for Strategic and International Studies, said at an event in November, using an acronym for unmanned aerial systems.

Limited tools for a growing threat

The challenge has been to adapt to the variety of drones that can be used for attacks using what has been a relatively limited set of countermeasures.

Some drones can be dealt with using traditional air-defense weapons. US-made Patriot missiles have been used against small drones in the Middle East, and US fighter jets have used air-to-air missiles against drones over Syria. But this often comes at outsized cost — Patriot interceptors cost roughly $3 million each, compared to drones that cost a few hundred or a few thousand dollars.

With larger drones, "you can see them. You can track them. You can shoot them down," McKenzie, who retired in April 2022, said at an event last year. "It's the smaller ones and the midsize ones that actually give you this problem."

The air superiority that US troops "have enjoyed" since World War II "no longer applies" in the Middle East, McKenzie added. "Things can appear in the sky that you may or may not be able to knock down over your own bases and installations, and that's a problem."

The drone threat emerged just as the US Army was getting rid of short-range air-defense units that had long been assigned to its divisions to protect against fixed-wing aircraft and helicopters. The Army retired its primary ground-based anti-aircraft systems after the Cold War and began deactivating many of its short-range air-defense units in the mid-2000s.

That was done to free up resources for other priorities — a tradeoff that Army leaders made "because they believed the US Air Force could maintain air superiority," according to a Congressional Research Service report.

By the mid-2010s, the service was hustling to fill its air-defense gaps. The Army's Asymmetric Warfare Group began training troops in Iraq to counter ISIS drones in 2014, and in 2016, the US Army in Europe cited a lack of air defense as a concern after witnessing Russia's use of small drones against Ukraine.

That work has accelerated over the past five years. In 2018, the Army reactivated the 5th Battalion, 4th Air Defense Artillery Regiment, returning a short-range-air-defense capability to Europe. By late 2022, that battalion had been fully equipped with the Army's new M-SHORAD system, a Stryker vehicle equipped with air-defense weapons. The Army plans to field several more M-SHORAD battalions in Europe.

In early 2020, the Army established the Joint Counter-small-unmanned-aircraft-systems Office to lead the military's development of training and technology to counter small drones, which it says "represent a rapidly proliferating, low cost, high-reward and potentially lethal and damaging capability."

Maj. Gen. Sean Gainey, the JCO's first director, said at an event last year its work is "mainly shaped on" what had been seen in the Middle East, "because that's really where most of our threat drone activity is and was."

Gainey has stressed the necessity of a "layered defense" to deal with cheaper, less sophisticated drones and with heavier-duty drones using appropriate tools, from directed-energy weapons to missiles. There are "several different type of threats, so you need layers, whether it's air-defense systems or counter-UAS-specific systems," which also have to be paired with the right training and tactics, Gainey said at a conference in Washington DC in October.

No silver bullets

The fighting in Ukraine has provided "reinforcement and validation" of what US troops have learned about drones in the Middle East, Gainey said at the conference, echoing Army leaders who say the drone war in Ukraine is influencing their planning — particularly for how to counter the one-way attack drones that Russia has used widely.

"In some cases, yes, what we're sending to Ukraine are also going to fit into our future plans," Douglas Bush, assistant secretary of the Army for acquisition, logistics, and technology, said at a press conference in early August.

Bush pointed to the new Low Altitude Stalking and Strike Ordnance program, which aims to develop a loitering attack munition that individual troops can carry into battle and to field it within two years. The Marine Corps has also been developing and employing loitering munitions.

The Army is also buying counter-drone weapons "quite extensively," Bush said. "A lot of that equipment, we're confident in it because of how it's done in the Middle East, frankly. That's where they've seen the most action."

Bush also stressed the need for different systems "given the diversity of threat" posed by drones.

"In some cases" —  such as Ukraine's anti-drone teams armed with machine guns and night-vision equipment — "low-tech works just fine," Bush said, adding that electronic warfare has been "highly effective" against small drones used by both Russia and Ukraine, "so we should learn from that." But higher-end threats, such as Iranian one-way attack drones, "show you do need, in some cases, more expensive missile systems," Bush added.

The JCO has tested a variety of counter-drone systems over the past two years, ranging from high-power microwaves to cannons and missiles. This year, the office has tested countermeasures for one-way attack drones that fly along preprogrammed routes. Next year, it plans to test weapons to counter attacks by drone swarms.

"I really look at the challenges being in the area of the speed, mass, and autonomy, where these systems are just getting faster, they're getting smaller, more autonomous, and they're able to potentially mass without a continuous link to a controller or a pilot," Col. Michael Parent, JCO acquisition and resources division chief, told Insider in a recent interview.

Massed drone attacks are a particular concern. Russian mass drone attacks, often coupled with missiles, have threatened to overwhelm Ukrainian air defenses, and the Pentagon worries about China launching such attacks on US forces in the Pacific. The Defense Department this week announced its own initiative to develop "multiple thousands" of "attritable autonomous systems" within two years in an explicit effort to counter China's advantage in mass.

"We have to continue to get after that evolving threat, because our adversaries are evolving to get faster, to build mass, and to be more autonomous," Parent said, emphasizing the need for a "system of systems" approach with a common command-and-control element to identify each threat and determine the best way to defeat it.

"There's no one silver bullet. There's no one system that we can call out and say, 'This is a system that's going to defeat every threat,'" Parent told Insider.

Bush said that the JCO is "doing a good job of seeing the landscape" of drone threats and that its work will inform "a broad push" to invest in both drones and counter-drone systems.

"The war is showing how much [drones are] here and are affecting the war every day. I think you can see it in videos every day. So we have to keep up," Bush said.