Here’s the thing that surprises people most about dual-use: how ordinary the technologies are.

Snapchat is a photo-sharing app for teenagers. It is also a company with deep expertise in real-time camera processing and face detection, on cheap hardware, in bad lighting. That is a fair description of a military targeting problem.

A fitness tracker counts your steps. In 2018, one of those apps published a global heat map that revealed the internal layout and patrol routes of overseas military bases — because soldiers go running too.

An ocean sensor deployed to monitor water temperature is a hydrophone. Its commercial and academic uses are countless. A hydrophone can also hear submarines.

Hardly any of those technologies were built with defence in mind, and in most cases nobody at the company ever considered it.

That’s the aperture we’re dealing with. Not a tidy sector of contractors and defence-adjacent firms, but a wide and largely unmapped set of ordinary companies holding capabilities nobody has ever asked them about — capabilities that may decide whether the country can defend itself.

What this means if you’re building something

Here’s a rough test. It isn’t official and it won’t get you a contract, but it will tell you whether this series is about you.

One — does what you build sense, move, compute, connect, power, or protect something? That covers more than it sounds like. Sensing includes cameras, microphones, thermometers, accelerometers. Connecting includes anything that keeps working when a network degrades.

Two — does it work in conditions someone didn’t design for? Bad light, poor bandwidth, cold, dust, no power, no operator. Robustness you built for ordinary customers is the exact property a military user pays for.

Three — would your product be more interesting if the stakes were higher? If your accuracy, latency, or uptime advantage is nice-to-have commercially but decisive when something depends on it, that’s a dual-use signature.

Four — could a hostile party use your data or capability against the people who generated it? If yes, you are already in this conversation whether you like it or not — and it’s better to know that before someone else works it out.

Answer yes to any of these and you’re in scope. Which raises an obvious question: if the aperture is that wide, why has almost nobody in it ever been approached?

That’s what the next three posts are about.

Next: originating and receiving are different skills.

This is drawn from my essay “The Dual-Use Dimension,” published in 2067 Journal. [Read the full piece →]