Traffic flow theory looks tidy on a whiteboard, but real roads don’t follow V D L arithmetic. Drivers open their following gaps faster than speed rises, so capacity peaks around 55 mph at roughly 2 000 veh/h/ln. Push limits higher and flow falls while crash energy soars. Because kinetic energy scales with the square of velocity (½ mv²), a 20 mph jump doesn’t give you 33 % more punch, it delivers nearly 80 % more. NHTSA data put it bluntly: fatal-injury odds about double for every 10 mph over 50 mph [1]. That’s an exponential climb in destructiveness, not a linear trade-off.
Higher limits also leak onto the streets that feed the ramps. The AAA Foundation’s 2024 before-and-after work showed a lasting uptick in operating speeds and speed-related crashes on arterials within a mile of interchanges after states boosted freeway limits [2]. Pedestrians and cyclists never set foot on the interstate yet bear some of the fallout.
Saying my analogy shuts down rational thought misreads what the analogy is doing. It's not a substitute for data but a framing device. I'm highlighting that different technologies share a core governance problem. When a private activity's danger rises faster than its utility, society uses regulation to keep expected harm below an acceptable threshold. This invites more rational analysis, not less.
If empirical data showed that 85mph highways or un-regulated assault rifles actually reduced third party harm, the analogy wouldn't block that conclusion, but instead lead to different regulatory settings. Your dismissal flips the burden of proof, hand-waving away the external-risk problem instead of engaging the numbers.
The gun analogy is serviceable once you zoom out from mechanics to externalities. An AR-15 and an 85 mph interstate both offer private utility but impose public risk that scales steeply—ballistic energy for one, kinetic energy for the other. Society uses licensing, background checks, or posted limits to push that expected harm below a tolerable threshold. Arguing that faster roads are safer because “cars clear out quicker” is like saying bump-stocks make rifles safer because the shooter finishes the magazine sooner: it flips the risk calculus on its head.
Think of operating a consumer-grade drone near people on the ground.
Private benefit: You get great aerial photos and save time compared with climbing a ladder or renting a lift.
External risk: If the drone falls from 100 ft it can hit a bystander with far more kinetic energy than if it falls from 20 ft (energy ∝ height, so the risk climbs steeply as you fly higher or faster or fly over people).
Regulatory levers: Aviation authorities cap altitude, require line-of-sight operation, limit flights over crowds, mandate geofencing near airports, and sometimes ask pilots to pass a basic safety test.
[1] https://www.nhtsa.gov/sites/nhtsa.gov/files/think.pdf
[2] AAA Foundation for Traffic Safety, “Uncovering the Spillover Effect from Posted Speed Limit Changes” (2024). https://aaafoundation.org/uncovering-the-spillover-effect-fr...