When does a sensor become a weapon? Networked warfare — this modern vision of combat as nodes of sensors connecting to grids of “battlefield effects” — has expanded both the kinds of information that go into decisions to firing a weapon and the ways in which people can be targeted. As the Pentagon actively brands its mission around lethality, some workers involved in making sensors have called into question their role in making weapons.

In a letter to Microsoft CEO Satya Nadella and president Brad Smith sent Feb. 22, Microsoft workers called on their executives to cancel the Integrated Visual Augmentation System (IVAS) contract because it was going to be used as a weapon. The contract, awarded in November and valued at $479 million, would provide up to 100,000 customized HoloLens units to the Army for use as a heads-up display on the battlefield.

The HoloLens, on which the IVAS system is being built, is a composite technology. It includes sensors, such as microphones and light sensors and a range of cameras. It includes a holographic display and lenses, creating a vision before the wearer that is mapped onto the world around them, as well as speakers. It is bound together with software and code, creating an experience in the real world not unlike that of playing a first-person video game, with useful information presented on a screen within the wearer’s field of view. The whole unit weighs slightly more than a pound.

It is the use of this technology for war, and especially for reducing the conduct of war to a video game-like experience, that receives special attention in the letter.

“While the company has previously licensed tech to the U.S. Military, it has never crossed the line into weapons development. With this contract, it does," reads the letter. "The application of HoloLens within the IVAS system is designed to help people kill. It will be deployed on the battlefield, and works by turning warfare into a simulated “video game,” further distancing soldiers from the grim stakes of war and the reality of bloodshed.

The letter writers are even more explicit in the next line, saying plainly, “Intent to harm is not an acceptable use of our technology.”

The word “lethality” has a central place in the Microsoft worker’s letter, which quotes “rapidly develop, test, and manufacture a single platform that Soldiers can use to Fight, Rehearse, and Train. This platform will provide increased Lethality, Mobility and Situational Awareness.” directly from the Army’s contract for IVAS. “Lethality” may scan as just another marketing or branding fad within the Pentagon, but it’s a word with an unsubtle meaning, and one that erodes any distinction between sensors or training tools and weapons.

The context around the quoted passage doesn’t do much to dissuade the notion that HoloLenses acquired in the IVAS program will be a weapons program. The Army states that the impetus for the tech is to “to overcome is an erosion in close combat capability relative to the pacing threats identified in the National Defense Strategy” and then later states “that near-peer threats have capabilities that match, and in some cases exceed the capabilities of American units.”

Specifically, the risk is stated as rivals using technology to “detect, target, and lethally engage before US forces become aware of their presence.” In an earlier era, we might have condensed that to “ambush,” though that doesn’t capture the distance as which sensors work today. The Army also specifically notes that while the fear is near-peer rivals using this technology, the technology itself is being developed both by militaries and by the civilian sector at large. As we already saw with cheap drones, a technology built for the civilian world and then adapted for war can have a surprise impact on the way militaries have to fight.

Before the contract was announced, Microsoft President Brad Smith defended Microsoft’s ongoing work with the Department of Defense in a blog post, saying in part that as a company “we believe in the strong defense of the United States and we want the people who defend it to have access to the nation’s best technology, including from Microsoft.”

In 2018, Google came under fire from its own employees, who objected to their company’s role in designing Project Maven, an artificial intelligence project that identified objects in drone footage. Google responded by sunsetting its work on Project Maven, and unveiling a set of principles for its AI work. The clash between Google’s executives and its workforce over military contracts sent shock waves through the tech sector and the Pentagon, and it was in light of this that Smith published his blog post, affirming that Microsoft would sell AI to the military. In his selling, he used one of the more common framing devices among the military, that having the best technology means saving the lives of the people doing the fighting.

Smith’s post also suggested that employees who objected to working on military projects could be moved off those projects. In the letter sent on February 22nd, the workers rejected to that framing on two grounds. The first is that, because HoloLens started as a civilian technology, workers found themselves in the uncomfortable position of realizing that a tool had been adapted to a weapon after the fact. The second objection was more universal, about the role of workers within a country whose military is an active presence across the globe

“As employees and shareholders we do not want to become war profiteers,” says the letter. “To that end, we believe that Microsoft must stop in its activities to empower the U.S. Army’s ability to cause harm and violence.”

In a Feb. 25 interview with CNN, Microsoft’s CEO responded to the letter, arguing that the responsibility for making decisions about military acquisitions was not on workers or companies individually, but on the people within a democratic society as a whole.

"We made a principled decision that we're not going to withhold technology from institutions that we have elected in democracies to protect the freedoms we enjoy," [Satya Nadella] told CNN Business at Mobile World Congress.

As Google discovered last year, as much as CEOs might like to imagine a clean division between their employees’ roles as worker and citizen, the people making their products may see no such distinction. For a Pentagon eager to court Silicon Valley, it is likely no longer enough to speak of how the technology it buys will protect war fighters. Instead, it may have to start talking about how to sell a mission of lethality to workers that never want their technology used with intent to harm.

Kelsey Atherton blogs about military technology for C4ISRNET, Fifth Domain, Defense News, and Military Times. He previously wrote for Popular Science, and also created, solicited, and edited content for a group blog on political science fiction and international security.

More In Sensors