A land mine is first a deadly surprise, then a menacing barrier, and finally a long-term problem for civilians after the war is over.

The Spider Networked Munition is, at least in intent, a means to deliver the first two effects without creating the persistent hazard of the third, and it does so through an unusual mechanism: it keeps a human operator in the loop. This month, the U.S. Army is spending more than two weeks testing an upgrade to the Spider, the landmine that isn’t.

The Army is quick to point out that human control means that Spider is distinct from a landmine, or what it refers to as “victim-activated systems.” That’s true so long as the human remains in the loop, and the Spiders are collected afterwards. But insisting that the networked nature of the latest Spider is what sets it apart from landmines makes it somewhat hard to distinguish what’s new about the Spider Increment 1A from earlier iterations of the weapon.

Spider is not a new weapon. The contract for Spider appears to have first been awarded in 2002, though the system faced some opposition at the time for its mine-like nature. Between April and June 2009, initial delivers of Spider were deployed to Afghanistan under an urgent materiel need request, with plans for either delivery and refinement by early 2011.

As described, Spider works towards the same explicit ends as landmines: it’s an obstacle whose strength comes from deadly explosions, rather than rigid physical barriers. This makes it useful as static defense around bases, and as a terrain-denial tool when used offensively. Tripwires and other sensors are still part of the overall package, but instead of automatically triggering the explosions, they send alerts back to the humans actively monitoring the not-a-minefield. Should the soldiers in charge of the Spiders decide the target is legitimate, humans then activate the Spider, which can release a variety of payloads. But a Spider is still mostly a means to set off explosives.

Spider is truly a system of systems, situated in a system. “Munition control units,” like low-polygon renders of sea urchins, are the not-mines of this not-a-minefield. Bristling with tubes and sensors, they hold the explosives or other payloads, sitting and transmitting and waiting. Those transmissions are carried by repeaters to a transceiver to a remote control unit, where the human responsible for the Spider watches and waits for alerts and action. It also relies on specific tactical internet, battle command systems, and GPS.

All of this adds complexity and labor to a kind of weapon that is traditionally set in place and left alone. In a curious detail that foreshadows the debate over human control over autonomous weapons, initial reports of the Spider system indicated that the weapon could be set to automatically detonate when the sensors were triggered, rather than wait for a human to authorize detonations. Nothing in the present, public-facing literature from the U.S. Army about Spider suggest it still works this way.

The United States is one of 34 countries that have not signed the Mine Ban Treaty, which would governs landmines that are passively triggered, but not explosive emplacements that are actively triggered, like claymores. Because nothing in war develops in isolation, the Spiders and claymores of American forces have their counterpart in command-detonated IEDs. (While the Mine Ban Treaty makes a distinction between remotely triggered anti-personnel devices and passive landmines, it includes IEDs in the prohibited category alongside traditional landmines.)

All of this brings us back to the actual meat of the latest iteration of the not-really-a-landmine Spider system. For the Spider Increments 1A, the system can receive and display digital maps. The control station can send “obstacle situational awareness” to a battle command tool (a feature promoted as part of the Spider package at least as far back as 2009). It has a better training manual. And it can use legacy off-the-shelf government munitions (in compliance with US landmine policy).

It is an incremental change, certainly. It is also a weapon system that requires battlefield networks to operate, and puts humans in the loop of lethal machines. Spider isn’t the future, but the way it operates suggests a path for nations that want to adapt more autonomous features in weapon systems, without forsaking human control. It’s possible, it’s just also a lot more labor intensive than the same systems set to work automatically.

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.

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