A.I. and the Next Generation of Drone Warfare

The Pentagon’s Replicator initiative envisions swarms of low-cost autonomous machines that could remake the American arsenal.
U.S. Deputy Defense Secretary Kathleen Hicks speaking at a podium with the U.S. Department of Defense seal on the front.
The initiative, announced by Deputy Defense Secretary Kathleen Hicks, is meant to accelerate the invention of military technology.Photograph by Alex Wong / Getty

On August 28th, the Deputy Secretary of Defense, Kathleen Hicks, announced what she called the Replicator initiative—an all-hands-on-deck effort to modernize the American arsenal by adding fleets of artificially intelligent, unmanned, relatively cheap weapons and equipment. She described these machines as “attritable,” meaning that they can suffer attrition without compromising a mission. Imagine a swarm of hundreds or even thousands of unmanned aerial drones, communicating with each other as they collect intelligence on enemy-troop movements, and you will begin to understand the Deputy Secretary’s vision for Replicator. Even if a sizable number of the drones were shot down, the information they’d gathered would have already been recorded and sent back to human operators on the ground.

In one sense, Hicks’s announcement, during an address titled “The Urgency to Innovate” at a meeting of National Defense Industrial Association, did not signal a wholly new approach. Five years ago, for example, the National Defense Strategy was already calling for major investments in artificial intelligence, noting that “we cannot expect success fighting tomorrow’s conflicts with yesterday’s weapons or equipment.” Since then, the D.O.D. has spent billions of dollars on artificial intelligence; last year alone, it allocated close to nine hundred million dollars to support nearly seven hundred A.I. projects. Still, as Hicks pointed out, many such technologies ended up cratering in the so-called valley of death—never getting adopted, even when they’d demonstrated success in the lab or the field. Her audience included numerous military contractors, whom she called on to “out-innovate our competitors.”

In another way, though, the Replicator initiative is a radical departure from business as usual in the Department of Defense. It is meant to accelerate the invention of military technology in order to change the way the United States fights wars and practices deterrence. Replicator, Hicks declared, would “field attritable autonomous systems at scale of multiple thousands in multiple domains within the next eighteen to twenty-four months.” As she envisions it, there will be “constellations” of these systems “flung into space, scores at a time”; pods of small, solar-propelled boats outfitted with sensors, trawling the ocean and relaying real-time intelligence; and “flocks” of aerial drones, some conducting surveillance and others carrying weapons. Instead of concentrating Defense Department resources on exorbitantly expensive and complicated equipment, which would have to be operational for decades to justify the cost, Replicator aims to deploy equipment with a much shorter shelf life, allowing for constant reinvention of technologies.

“In my entire career, the military strategy has been to build these exquisite and expensive systems, which are incredibly effective,” Chris Gentile, a retired Air Force lieutenant colonel who is now the vice-president of EpiSci, a defense contractor that develops autonomous systems, told me. “I flew stealth fighters in the Air Force. I flew the F-22. It’s an amazing airplane, but we only bought a hundred eighty-seven of them.” (Just last week, the Times reported on the Navy’s continued investment in large, lumbering warships that tend to become outdated before they’re even built.) “When we look to the future, we just think that this economic model doesn’t work—so we’re going to increase the mass, just the number of physical things, that we’re able to bring into the theatre.”

Thomas Hamilton, a physicist at the RAND Corporation, a think tank that often conducts research for the U.S. armed forces, calls this approach iPhone economics. “It’s the idea that, while the cost of developing the software is billions of dollars, the cost of manufacturing each iPhone is very low. From a military point of view, there’s a huge advantage if I send out a lot of things that are cheap to make but have expensive software—so, if the enemy shoots them down, they haven’t destroyed any of my expensive software.”

For a number of years, Hamilton, along with colleagues at RAND, has been advocating for using inexpensive aerial vehicles in concert with one another. He remembers watching as the cost of microprocessors went down and their capacity went up, until the idea of drone swarms, which the military had been kicking around for more than a decade, seemed feasible. “You can have ten or twenty or fifty drones all fly over the same transport, taking pictures with their cameras. And, when they decide that it’s a viable target, they send the information back to an operator in Pearl Harbor or Colorado or someplace,” Hamilton told me. The operator would then order an attack. “You can call that autonomy, because a human isn’t flying every airplane. But ultimately there will be a human pulling the trigger.” (This follows the D.O.D.’s policy on autonomous systems, which is to always have a person “in the loop.”)

Inadvertently, the war in Ukraine provided proof of concept that many small drones can overwhelm a sophisticated fighting force. As Russia rolled out missile systems intended to bring down expensive Western planes and munitions, Ukraine launched much cheaper unmanned aerial vehicles, controlled by human operators, to take them out. The drones gave the Ukrainians a tactical advantage while also enabling them to spend less to do more. “You’re shooting a quarter-million-dollar missile at a forty-thousand-dollar drone,” Gentile said. “The objective here is to win the cost battle—to make sure that, at a resource level and a money level, you’re coming out positive on the trade.” Individual Ukrainian hobbyists have also been steering small quadcopters, some with wingspans no larger than twelve centimetres, to crash into and destroy Russian weapons. By one estimate, Ukraine is losing ten thousand drones per month while still being able to prosecute the war—a real-time demonstration of attritable technology.

In her announcement, Hicks invoked the People’s Republic of China (P.R.C.) a number of times, leaving no doubt that it is, as Hamilton told me, “our pacing threat,”—the adversary whose aggression the United States most fears. “Replicator is meant to help us overcome the P.R.C.’s biggest advantage, which is mass. More ships. More missiles. More people,” Hicks said. A week later, in a speech at a conference sponsored by Defense News, she asked and then answered the question that the timing of the Replicator initiative raised: Was there new intelligence that suggested an imminent attack on Taiwan or U.S. allies in the Indo-Pacific? While she said there was not, Replicator’s 2025 target corresponds to when some military analysts believe China could launch an attack on Taiwan. “We must insure the P.R.C. leadership wakes up every day, considers the risks of aggression, and concludes, ‘Today is not the day’—and not just today, but every day, now and for the foreseeable future,” Hicks said.

The biggest obstacle to the Replicator initiative’s success in the Pacific may be a mismatch between geography and technology. At the moment, Ukraine’s small aerial drones have limited range and power, and most of them are either made in China or use Chinese components. By contrast, American-made surveillance drones, like Northrop Grumman’s Global Hawk, which are being used by NATO forces in the Ukraine conflict, cost millions of dollars and are the size of manned aircraft, in part because they can stay in the air for more than a day. Even midsize drones can cost more than a million dollars. Neither is likely to be considered “attritable.” So, until American companies—or the government itself—are able to produce relatively inexpensive drones that can fly long distances, China will have the advantage in the air. As Stacie Pettyjohn, the director of the defense program at the Center for a New American Security, a nonpartisan think tank, told me, right now “it would be much easier for Chinese ships to spit out some of these small drones, or some of their ground forces to have them,” she said. “You would expect to see them saturate the battle space.” Those drones can then send back intelligence to the mainland, she said, where the Chinese military has long-range missiles that can reach Taiwan.

Aerial swarming drones are just one part of this new push. The Navy is developing a fleet of small, unmanned vessels, some not much larger than a child’s toy, and submersibles that can locate and disarm underwater mines. It is also pursuing an agreement with the Air Force so that each branch can control the other’s combat drones. The Army has long used autonomous ground vehicles, and is now testing quadrupedal “robot dogs,” armed with six-and-a-half-millimetre rifles that can be fired by soldiers off-site. The Air Force is aiming to build a thousand “robotic wingmen” to assist manned aircraft. Hicks also envisions launching thousands of “smart satellites” that use A.I. to navigate and track adversaries. Whether these technologies remain restricted to the battlefield, or get repurposed in new and unbridled ways—for example, in domestic surveillance by an increasingly militarized police force—remains to be seen.

Achieving the vision Hicks laid out for Replicator is a moon shot that will require a new mind-set in the Defense Department, her spokesperson, Eric Pahon, told me. “The D.O.D. has been doing things the same way since World War Two. Occasionally, when we have a conflict, we innovate. But what we’re looking at here is being able to change the culture to keep up with not this strategic competition but also modern technology. We can’t be on these ten-to-twenty-year development cycles. That’s not going to work.” Where there once might have been a thirty-day process for submitting a form, Pahon said, the department could potentially shorten that period to five. In Hicks’s speech, she said that they had already reduced the time it will take for the delivery of new technologies.

Replicator still might end up in the valley of death, especially given the pressure created by its accelerated timeline. “You’ll never see the Secretary or me rolling out a ‘Mission Accomplished’ banner when it comes to innovation,” Hicks told the trade group. But she has started the clock, and it is counting down. ♦