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M65 Atomic Cannon

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I was personally more astounded when I first discovered the Davy Crockett nuclear warhead recoilless rifle:

https://en.m.wikipedia.org/wiki/Davy_Crockett_(nuclear_devic...

When I told my dad (who grew up in the Cold War) about the weapon, he said "Oh yeah, I had the toy model version."

I'm often astonished any civilizations survived the Cold War.

Even better is the name. What a good old cornpone American name for... just wow.

The cold war does make me wonder about quantum immortality. Maybe consciousness just happens to exist here in a timeline where consciousness still exists.

Per Wikipedia:

>Howze is credited with starting the convention of naming US Army helicopter types after Native American tribes, because he found the names suggested by the manufacturers too insipid. The Bell H-13, which had already been in service for some years, was renamed "Sioux" at his suggestion and the tradition continues to the present day.

https://en.wikipedia.org/wiki/Hamilton_H._Howze

Yeah. No guidance, no nuclear codes for authorization, no way to abort the launch, nothing but a "handle with care" message on the nuke itself. The only reason humanity survived is nobody dared to actually use this stuff.

They also made backpack nukes:

https://en.wikipedia.org/wiki/Suitcase_nuclear_device

The USA also has chemical weapons stockpiles that haven't been fully destroyed to this day. The Honest John rocket could be fitted with sarin warheads:

https://commons.m.wikimedia.org/wiki/File:Demonstration_clus...

* No nuclear codes for authorization*

It had a 3-digit arming code, set by turning three rotary switches with a screwdriver. "Code must be correct or weapon will dud", says the comic-book training manual.

Is there a scan of this manual online somewhere? I'd love to read it but not sure what to search.

I can't find it any more. It's probably lost in the Internet Archive somewhere. It was done by Will Eisner, who also did many of the long-running US Army series of preventive maintenance comic books.[1] Those are still being published, 66 years on.[2]

[1] https://en.wikipedia.org/wiki/PS,_The_Preventive_Maintenance... [2] https://www.logsa.army.mil/#/psmag

You have a range of 2-4km, reaching that range in a couple seconds, and a lethal range of several hundred feet. Why do you need guidance, or a way to abort after launch? If you don't want it to go boom, don't launch it in the first place.

And we're working on destroying the chemical weapons. It's just tricky. Some of the chemical weapons were corrosive, which makes them difficult to move.

The Davy Crockett made an appearance in some 1959 plans for an Army base on the moon (https://en.wikipedia.org/wiki/Project_Horizon):

> The base would be defended against Soviet overland attack by man-fired weapons:

> Unguided Davy Crockett rockets with low-yield nuclear warheads > Conventional Claymore mines modified to puncture pressure suits

Non-mobile: https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)

It boggles my mind that they were able to miniaturize a weapon to that extent ~60 years ago.

It’s easy to think of the technology[0] portrayed in games like Fallout as a parody of the time but then you see something like that.

[0] https://fallout.fandom.com/wiki/Fat_Man

Video of the Crocket firing https://youtu.be/eiM-RzPHyGs?t=216

Actually quite a modest bang by nuclear standards.

If you are driving across Kansas on I-70 you can take a stop in Junction City at Freedom Park. It is right at the exit on the south side. A short climb up the hill past some other artillery gets you to the M65. It’s more or less targeting Salina which is a 20 minute drive down the interstate.

You can get right up to it. And it hurled nuclear warheads a 20 minute drive down the interstate.

Now that I double check the satellite photos, it isn’t so much aimed at Salina as Hope, which seems fitting.

I found this footage of the first Chinese nuclear test astounding when it was posted on YouTube 13 years ago:

https://www.youtube.com/watch?v=9xoHbBkUGSQ

This guy was achieving a peak that few of us will ever experience:

https://youtu.be/9xoHbBkUGSQ?t=200

The music in that video is incredible. I love the whole thing, haha.

For the record, that's a segment from the documentary movie Trinity and Beyond: The Atomic Bomb Movie [1]. It's an incredible documentary and I thoroughly recommend anyone interested in the development of atomic weapons finds a copy of it.

[1]: https://en.wikipedia.org/wiki/Trinity_and_Beyond

Growing up in Germany it was weird to think if these weapons or similar ones were ever used it would probably mean that Germany and probably parts of Europe would be destroyed. Pretty scary.

I’m fairly sure that if these weapons are used then a lot more than Germany would be destroyed.

That was a painful question. If soviet tanks had advanced through Europe, would the USA had responded with limited war or would had trigger the whole MAD thing?

The answer wasn't as clear as with a ICBM attack, that was a much more irreversible decision.

FWIW the neutron bomb was developed for use against Soviet tanks.

The smaller tactical nukes were designed around the idea of being rapidly deploy-able area denial weapons to halt a Soviet land invasion.

Note these were developed before MAD was really a thing. The Soviet nuclear arsenal in the early 50's was still pretty small, they had few bombers and ICBMs wouldn't be deployed till the end of the decade. On the other hand, they had a gigantic conventional army, and an obvious geographic advantage over the US in a convetional war fought in Europe.

So US strategy was build around using their nuclear advantage to stop a conventional Soviet invasion of Europe before it could get out of Germany. Hence the development of tactical nuclear weapons like the M65, which seem bizarre to us today, as we're used to thinking about nuclear war in terms of MAD, but made sense (or at least, more sense) at the time.

The M65 and the Davy Crocket were designed to stop a Soviet tank invasion through the Fulda Gap[1]. NATO knew the Soviet army had a numbers advantage. Tactical nukes were developed to stop a mechanized invasion with a smaller force. The idea was that a hot war could start and both sides would avoid the use of strategic nukes, since this would be a civilization ending event.

1. https://en.m.wikipedia.org/wiki/Fulda_Gap

No, that's not how nuclear weapons work.

Generally, if you attack another country with nuclear weapons today I feel like you’d swiftly draw the world into a nuclear war?

This discussion is about the 1950s, not today. And no, that's not a guarantee.

The Wikipedia page has a picture of the cannon with a nuclear explosion seven miles away. Isn't Germany larger than 7 miles wide, not to mention I thought it was part of Europe?

If things had ever gotten to the point where atomic cannons were being fired in anger, there would have been a lot of nuclear weapons flying around.

There are different grades to nuclear weaponry. A lot of the weapons in discussion here are tactical: something like the Davy Crockett can blow up only a city block... but more realistically would be used to wipe out part of a military base or maybe one or two ships. 100kT or less, Davy Crockett being ~10 Tons (or 0.01 kT)

The "strategic nukes" on the other hand, are city-destroyers. 10Megatons or bigger, 100x or 10,000x larger than tactical nukes.

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In effect: a tactical nuclear weapon is fired even if there are friendly forces nearby. In contrast, strategic nukes are fired when you want to kill everybody in an area.

Even if a serious war started, no sane person would ever dare to touch strategic nukes. Once strategic nukes start flying, its pretty much the end of the world as we know it. The only response to a strategic nuke is to follow through with MAD.

Tactical nukes are small enough that MAD may not be triggered. It would be an unprecedented escalation, but military generals around the world would quickly try to draw the line at "tactical nukes only". The problem is that no one has really drawn a hard line at what makes a nuke "strategic" or "tactical"... there's a smooth curve from 10 Tons (Davy Crockett) all the way up to Tsar Bomba (50,000,000 Tons). So there's a big fear that starting even with small tactical weapons would lead to a path of escalation towards the biggest nukes.

The real problem is that if you hear a big boom and your communications fail, how do you know the Russians haven't launched at the US mainland?

You're a commander of a small airfield in the Pacific and the last you heard from the US was that tactical nukes had been used in Europe. Now, communications are down. You have a bunch of planes ready to go, and if there's missiles or planes headed your way, you'll die pointlessly if you don't put them in the air. You have a letter from the President authorizing you to launch in this situation.

Now what?

Stanislav Petrov was in a similar conditions: https://en.wikipedia.org/wiki/Stanislav_Petrov

> You're a commander of a small airfield in the Pacific and the last you heard from the US was that tactical nukes had been used in Europe

If you hear the boom and you're not dead... then it was probably tactical.

Strategic nukes aren't launched one-at-a-time. They'll be launched thousands-at-a-time. You're simply dead, you'll be pulvarized by multiple ICBMs before you even know what hit you.

The plan is to launch your strategic nukes in retaliation BEFORE they hit their targets. Alternatively, you have enough secret nuclear submarines to launch your strategic counter-attack after-the-fact (even if the mainland is destroyed).

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The launching of any ICBM would probably trigger the end of the world as we know it. ICBMs fly at such speeds that they cannot be reliably stopped: they're basically spacecraft. Once launched, their target is effectively going to be destroyed within 10-minutes or so.

The real risk of strategic weapons is misidentifying a flock of birds as an ICBM (or other such technical glitch).

I was garbling a scenario from Ellsberg's book. I believe the time period in question was the 50s-early 60s (the same period where these tactical nukes were popular) when MAD was being enforced by bombers, not ICBMs.

According to Ellsberg, there was a period where there was no actual plan to defend Europe by other means than massive nuclear retaliation.

https://www.amazon.com/Doomsday-Machine-Confessions-Nuclear-...

There are YouTube videos.

You're probably too young to remember, but Germany was a very hot frontier at the time and the most probable point for battles on the ground as opposed to ICBMs or subs.

That seems anachronistic? US ICBMs came along late 50s, I believe. Battlefield weapons like this just weren't in the same context as what we think of as MAD with thousands of missiles set to destroy the world. My original point was that in a scenario that they were used, the world wouldn't be blown up with city-killers.

I think yes. Even after the city killers, dogma dictated Soviet armour would pour in from the Warzaw pact. Then the tactical nukes come out. You can’t hit moving tanks with strategic nukes. Incidentally Soviet tank dominance was why the US developed attack helicopters.

He didn't say the world, just Germany and [other] parts of Europe and it's a probable result indeed. You don't make a cannon to shoot just once.

The joke was that towns in Germany are only two kilotons apart.

Another fun nuclear weapon that would have destroyed Germany is Blue Peacock. It was a series of nuclear mines placed across West Germany to be detonated if the Soviets invaded. They used chickens to keep the mines warm in cold winters.

Nuclear mines has to be the dumbest weapon idea I've heard of. Using nukes for scorched earth tactics would make the locals hate you forever regardless the outcome of the war. It would be a powerful propaganda tool for the other side.

The general assumption was that if Russia ever had attacked then Germany would have been the battlefield. Nobody in Germany expected the country to survive in that case. It sort of would have made sense to try to stop the advance at any cost.

Even if the country doesn't survive, people will.

One problem with nuclear mines is that they're unattended. If some crazy circumstance happens where the US loses control over the area, but it's not war, then you suddenly have a bunch of hidden nukes lying around that could detonate.

Another problem is that if the Soviets ever found them then they could use them as effective propaganda. If even one of those mines goes off, then they could say that they're liberating the Germans from their American oppressors. After all, you don't nuke your own ally and a nuclear detonation is hard to hide.

Doesn't matter about propaganda if everyone is dead and there are no locals any more.

That was really the defining philosophy of the Cold War nuclear threat escalation; total extermination of millions of civilians in as short a time as possible.

Just in case there's any doubt: the British government went as far as ordering ten prototype mines, but they stopped short of installing them and cancelled the whole thing because it was just too insane. And the chicken thing was just a proposal, no chicken was deployed.

As always, the problem with antiquated arms is: you can't afford the ammunition.

What a cool machine, and a goofy concept by modern lights. I'd love to go look at how that's actually built.

You think that's crazy, you should see some of the other things the Army was working on at around the same time.

At least the M65 could lob its atomic payload a respectable distance away from the people operating it. That wasn't as true of the "Davy Crockett" atomic rifle (https://en.wikipedia.org/wiki/Davy_Crockett_%28nuclear_devic...), though, which could fire an extremely low-yield (equivalent to 10-20 tons of TNT) atomic warhead a distance of 1-2 miles, tops. That would probably have been far enough to avoid killing the operators of the weapon when it went off, though if the wind was blowing the wrong way they would have had some nasty exposure to radiation.

And beyond even that was the so-called "Special Atomic Demolition Munition" (SADM: https://en.wikipedia.org/wiki/Special_Atomic_Demolition_Muni...), which used the same warhead as used on the Davy Crockett, only this time packed into a backpack (!). The idea was that a soldier would either hump the backpack to the target on foot or be air-dropped in with it, plant the backpack near a strategic target, set a detonation timer on it, and then run like hell. Foreign Policy magazine ran a good article about what it was like to be one of the guys tasked with this mission a few years back (https://foreignpolicy.com/2014/01/30/the-littlest-boy/). Spoiler alert, it was kind of a stressful job.

Heh, I was just reading up on this yesterday while doing some recreational research into atomic weapons testing in Nevada. Look on Google Maps here to see a thousand craters [0]. Turns out, they even give tours once a month [1].

[0] https://www.google.com/maps/@37.1496894,-116.0575635,3767m/d...

[1] https://www.nnss.gov/pages/PublicAffairsOutreach/NNSStours.h...

Here is some good info about minimum payload (16kg) needed for fission

http://nuclearweaponarchive.org/Nwfaq/Nfaq4-2.html

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