Thanks to decades’ worth of cultural pressure on the international stage, most nations view the use of nuclear weapons in war as a reprehensible act. Today’s nuclear nations, by and large, ascribe to a model of deterrence: Put simply, our nukes stop them from using their nukes. Although posturing can get quite a bit more complicated than that, mutually assured destruction remains the primary mode of prevention when it comes to nuclear war. In the minds of many, a single nuclear strike is conceptually synonymous with a global nuclear war, simply because we’ve spent so long operating under the assumption that the response to one nuke is more nukes.

But that mindset wasn’t always the prevailing one in the national security community. For a time, the tactical use of nuclear weapons seemed like a feasible strategy in the event the Cold War turned hot. The idea wasn’t to strike the Soviet Union with a cascade of ICBMs that would wipe the nation off the planet, but rather to utilize small nuclear weapons as a highly effective means of waging war on an otherwise conventional battlefield.

If this is sounding a bit like the Fallout game series to you, there’s a good reason for it. The “mini-nukes” and other nuclear-powered weapons throughout the series are largely based on nuclear programs (or aspirations) from America’s 1950s, tying in with the game series’ overall aesthetic. In fact, if you think of the way the video games incorporate these nukes, you may be surprised by how frivolous the U.S. government really was with small nuclear devices.

How frivolous? One American Special Forces unit was tasked with learning how to ski down the Bavarian Alps with 60-pound nuclear weapons  strapped to their backs.

“It skied down the mountain; you did not,” said Bill Flavin, who commanded a Special Forces team tasked with the operation. “If it shifted just a little bit, that was it. You were out of control on the slopes with that thing.”

It only gets crazier from there. The backpacks those Green Berets were tasked with ferrying down those treacherous slopes were called Special Atomic Demolition Munitions, or SADMs. The U.S. government designed a variety of these man-portable nuclear weapons with destructive yields that ranged from 100 tons of TNT to 1,000 (.1 to 1 kiloton). They weighed approximately 59 pounds and were always meant to be delivered via a two-man team.

Although the deployment of the weapon could really be handled by just one special operator (these weapons never reached the conventional forces), nuclear doctrine dictated that no single person—other than the president—ever have the means to detonate a nuclear weapon on their own. As a result, each special operator was given one half of the detonation code and both would need to input said codes in order to start the countdown on the weapon.