Could the Average Person Be Guided to Defuse a Nuclear Bomb?

Most of us like to believe that if we were ever caught in the midst of a world-altering disaster, we'd rise to the occasion as a real-life action hero: Stay calm, do what’s necessary, save countless lives, and still make it home for dinner.

What might such a hero end up doing? Disarming a nuclear bomb. Imagine a ragtag group of villains, led by an eccentric but captivating figure (think: Nicolas Cage), seizing the most devastating weapon ever created by humankind... which is about to explode... and you’re the only one there to stop it. With a few basic tools, an expert on the line, and a bead of sweat on your brow, what are the chances you’ll succeed?

Bombs 101

For fairly obvious reasons, many of the intricate details about how nuclear weapons function are classified. If there were a trustworthy WikiHow guide for disarming a nuke, there’d likely also be one on how to make your own, and that’s definitely not a scenario the world needs.

That said, most nuclear bombs are believed to share a similar setup in their operation; specifically, they are “armed” (or activated) by devices known as permissive action links (PALs). These are designed to be nearly impossible to bypass. Nuclear physicist and weapons inspector Peter D. Zimmerman once quoted an unnamed weapons designer who remarked that circumventing a PAL would be 'as complex as performing a tonsillectomy while entering the patient from the wrong end.'

In movies, this often gets depicted as entering codes or having two military officials turn keys simultaneously—essentially a system to ensure that the bomb can’t accidentally detonate or be armed for malicious reasons.

“The weapons in the U.S.’s arsenal—and likely in most others—have many built-in features to permanently or semi-permanently disable the device if there is an unauthorized attempt to arm it,” Areg Danagoulian, an associate professor of Nuclear Science and Engineering at MIT, tells Mytour.

What this means is that, hopefully, it’s much easier to disarm a nuke than to arm one. They are designed to be activated only if every step is followed precisely, with multiple failsafes in place to prevent anyone from using them for nefarious purposes.

To Detonate or Not to Detonate

These safety measures are logical, as one of the core principles behind nuclear weapon design is making sure it doesn’t detonate when it’s not supposed to. If the primary function of a bomb is to explode, then the second most crucial function should be to prevent it from exploding when it shouldn’t.

If you’re incredibly fortunate, disarming the nuclear bomb you’ve encountered might be surprisingly simple. The B61 bomb, which serves as the model for most of the U.S.'s nuclear arsenal, is said to have a 'command disable' feature, according to Danagoulian. 'If this mechanism is triggered, it sends a powerful current that destroys the bomb's electronics, rendering it virtually useless.'

The nuclear bomb equivalent of an emergency stop button on an escalator might be too good to be true, but the next best thing is akin to entering the wrong PIN into your phone too many times, causing it to freeze.

“According to some sources, if you enter the wrong arming digital sequence—what you might consider a nuclear code—a certain number of times, the bomb’s electronic system will lock, or potentially misfire and destroy the weapon,” says Danagoulian.

The Verdict

While this might sound unsettling, Danagoulian notes that if this occurs, it won’t result in a nuclear blast. Instead, it would likely cause a localized chemical explosion that would disable the bomb, with minimal risk to anyone—except the person trying to tamper with it.

A certain death probably isn’t what you were expecting as your reward for trying to save the day, but it’s good news for everyone else. There’s something almost poetic about the idea that, in the most critical moments, millions of lives could be spared by simply frantically pressing all the available controls until the bomb gives up and destroys itself. The only force more powerful than a nuclear bomb: mindlessly mashing buttons in the hopes that it all works out.