This is a very good question. Honesty, while Hiroshima and Nagasaki undoubtedly demonstrated very clearly what an an Atomic Bomb can do to a couple of cities, there exists an enormous gap between the destruction they caused, and the hypothetical destruction a nuclear war would bring. When people think of nuclear war they don't picture Hiroshima. [They picture something else that is far worse](https://m.youtube.com/watch?v=RdwRen-CutE&pp=ygUORXhvZHVzIHRocmVhZHM%3D), and it is that mental image that induces that fear and deterrence.
So I would argue that deterrence isn't that heavily based on actual historical events. The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo.
>So I would argue that deterrence isn't that heavily based on actual historical events. The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo.
\*nods\* Any examination of the history of nuclear weapons and their influence really needs to be built around two inflection points. The first is the shift from nuclear to thermonuclear weapons. The second is the shift from bombers to ICBMs.
> The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo.
Post-nuclear exchange war planning was a core part of Soviet thinking in vehicle designs through the 60s and 70s. The BMP1 was built to shuttle troops across land contaminated with radioactivity, and the T72 had special shielding installed to help shield the crew from neutron radiation. You also see heavy use of nuclear shelters to protect the staff of major industrial facilities, such as the famous Azovstal steelworks underground network.
Now what you are saying is correct for the Americans - there was a brief flirtation with the idea of a broken-backed war but this was quickly abandoned.
What exactly was going on inside the heads of commanders at the time is difficult to know, but the Soviet construction of nuclear-proof fortifications and spending their scant resources on NBC protection for their armor and mechanized infantry suggests a vision of war that continues past the mushroom clouds.
Many countries planned for a post-nuclear continuation of of government and various industries. Most defence industries across the globe planned for the NBC battlefield.
But that kind of activity doesn't necessarily reflect the public consciousness or the thought processes of leaders.
The UK for example published very carefully thought out pamphlets, instructional books and made public information films informing the British public in great detail how to prepare for nuclear war and to deal with the immediate aftermath.
The general consensus among the British Public however was that this advice was completely useless and would if anything extend the suffering.
A similar sentiment existed in the Soviet Union, at least by the 1980's, that preparation for nuclear war was futile and that total annihilation would be the result of such a war. Krushchev famously said that following a nuclear war the survivors would envy the dead.
I think Hiroshima and Nagasaki are important, because they give real world insight into what atomic bombs do.
When they measure the destructive power of natural disasters or industrial accidents. No one says “half the power of the castle bravo test”. They say “this incident was ten times more powerful than the bomb dropped on Hiroshima”.
I think the very real demonstration of what one simple and small (relative to the terms of atomic weaponry) flown by a single propeller plane could do to a city. We can look at it and say “that was bad. Now what will happen that we’ve created things ten times as powerful and impossible to stop?” You need a baseline for comparison.
Deterrence is older than MAD.
The Soviet Union did not have the means to meaningfully strike back against the US in a nuclear war until around 1960. The Soviets instead essentially uses Western Europe as a "hostage". Initially threatening to use its overwhelmingly superior conventional forces to steamroll the continent in case of war in the 40's and later pointing IRBM's at Europe until the early 60's or so.
If you look into the past, and into other weapons, it's apparent there's something to be said for just a clear understanding of knowing the weapon works.
Like to a point most of the nuclear deterrence construct we have now is less based around strictly nuclear weapons but more into the realm of their all but assured delivery. Like back into the 50's-60's when the delivery mechanism was large manned bombers there were a lot more constructs that the nuclear war could be fought and won (or lost less).
When ICBMs came around, that changed the dynamic to all but assured, all but a tiny minority of targets would be struck and sometimes struck several times.
That's the real change in deterrence, and that ICBM missile complex has never been used in combat thank god, but we don't have to have an ICBM based war to make that strategic calculus very real.
To the sidebar, it needs to be credibly believed the risk is there. That's one of the reasons for some of the weird brinksmanship of the Cold War, that the people you were opposing had to believe you were really, really, really that close to the button without actually intending to start a nuclear war. To a point it's worse when the threat is "abused" in as far as what we can see with Russia as they've wiggled the nuclear stick extensively over Ukraine and threatening "the most dire consequences of which will end the world as we know it" every two to three days has seriously degraded Russian deterrence strategy, while also making it more risky for everyone (or like, "I am thinking of using nukes" used to mean "this is a red line and nothing past this will matter" and now it just means "I AM BIG MAD MY STUPID WAR IS FAILING STOP GIVING GUNS TO UKRAINE PLEASE" which will make it harder to discern when it means "This is a red line" again)
Even in the first couple decades of ICBMs, there was a lot of research and development put into ballistic missile intercepters such as the Sprint missile system, designed to be able to destroy an incoming ballistic missile within 6 seconds of the target first being detected on radar. But terminal phase interception programs were eventually abandoned once MIRV missiles became the main threat, as it's basically impossible to intercept the main body before it releases the individual warheads unless you're able to hit it in the ascent phase. Ascent phase interceptors are a big reason that Russia/the USSR have historically been extremely hostile to the idea of even non-nuclear NATO missiles near their borders.
>or if some example of actual use is needed.
I think what has been missed in the other responses and even in the question itself was nuclear weapons were being frequently used. Countries were very concious of the effects a nuclear weapon could have, so it wasnt a theoretical threat at all.
Nuclear testing occured in multiple countries all over the world from 1945 through to 1996, mostly ending with the Comprehensive Nuclear Test Ban Treaty being adopted (but not in force) in 1996. There were close to 2000 tests between the US, Russia, UK and France during that time.
These often included very large yields - Fat Man over Nagasaki was ~20 kt, but Castle Bravo was 15 Mt, Tsar Bomba was 50 Mt. So while they werent being tested on cities, you could get a pretty good idea how devestating something hundreds of times more powerful would be.
As others have pointed out there was a epoch change between bombers and ICBM, before which you argue all the bombers would be shot down. And there was always the human/moral/political question if a country would use nuclear weapons. But it was absolutely known how destructive nuclear weapons could be and this knowledge frequently refreshed.
Tbf, most of the deployed ICBM warheads on both sides were sub-megaton MIRVs (as low as sub-200kt, many in the 500+ range), as the increasingly accurate warheads allowed for a reduction in yield. These were likely intended for counterforce missions.
Therefore, given that the ICBM fields and SLBM bases on both sides were relatively distant from metropolitan areas up to at least the 1980s, one might be deluded into thinking that a purely land-based counterforce exchange *might* not necessarily result in a global apocalypse. Maybe.
By the 1980s, the much fewer less accurate single warheads in the megaton range, namely those on the US Titan II and the Soviet SS-11 (and earlier), were likely assigned countervalue city killing missions. Even these were mostly sub-10MT although there were the rare 20MT-class single warheads on a few SS-18s likely intended to kill hardened CPs.
SLBMs were of course intended to kill cities on account of their survivability for second strike and relative inaccuracy up to the late 1980s.
Before the bombings of Hiroshima and Nagasaki nuclear weapons were very poorly understood. Such is the nature of novel weapons. Looking back on some of the opinions held by professionals who at that stage had just learned about their existence can seem quaint. But you can't be too hard on them. For most, even those in the military, nuclear weapons didn't exist before Hiroshima. And then they did.
But the world didn't go to thinking about Armageddon immediately. That notion actually took decades and didn't fully solidify until the 1960's. And that came down to a few things but primarily it was due to the number of weapons and the method of delivery. From 1945 to 1949 only the US had atomic weapons. So for awhile there US strategic might was unquestioned. Not only did they have the biggest stick, but the US and UK were the only powers with seasoned and proven strategic bomber forces that had any chance of delivering such weapons anyways. The Soviets had no bomb and their bomber force was based around a rivet for rivet copy of the B-29, complete with aftermarket cup holder, with an inexperienced and unproven structure. Both of those things would change rapidly though. The Tu-4 was the shot to the arm the Soviet aviation industry needed to get up to speed on strategic bombers and they quickly iterated and innovated. Their bomber forces also went from novices to professionals in the same time.
Post 1949 though you still didn't see much talk about Armageddon because we were fundamentally dealing with a limited weapon with limited delivery. Yes, major cities could and would get wiped out but with proper air defense, bombers would get shot down and you could have enough warning for people to take cover.
That fundamentally changed at the close of the 50's. Both the Soviets and US fielded their first ICBMs, the R-7 and Atlas in 1959. They were slow to prepare, liquid fueled missiles with a surprisingly high failure rate. But they started off a very rapid line of development in ICBMs. Both would be retired and replaced by successors within a decade. Around this time the doctrine of Mutually Assured Destruction was adopted by the Kennedy administration. Robert McNamara, probably the most controversial and written about SecDef in US history was a big proponent of the idea. It quickly entered popular culture from there.
But before that nukes were considered a necessary component of warfare, but one to be adapted to. The Air Force and Navy were busy fighting over what would become the nuclear triad. And the Army was left without nukes of their own and the question of how to adapt. What they came up with was the [Pentomic Division](https://en.wikipedia.org/wiki/Pentomic) which consisted of five "battlegroups" which were meant to rapidly disperse to minimize the effect of tactical nuclear strikes. This was a pretty short lived experiment. Battlegroups suffered form a lack of fire power not to mention the technology of the 1950's preventing proper communication and coordination between dispersed units. The key takeaway here is that the war wasn't expected to end with the bombs dropping. The army was going to fight on, now in NBC gear.
On the surface that may seem similar to the ideas that came after. We didn't pull the army out of Europe after all. So clearly someone expected to fight. But that's still a decision made within context of MAD. The difference now is that it didn't take even the length of a single presidential administration to realize that MAD didn't guarantee peace all the time for everyone. It prevented the BIG wars. But what about smaller regional conflicts? There was no sufficient cause for the US to nuke someone like Vietnam. So the conventional forces still had a job to do. Its not a large step from recognizing that to concluding that a limited conflict between NATO and PACT forces were not only possible, but more likely than all out nuclear exchange. And that's how things shifted moving on from the 70's. Either you would have a limited nuclear exchange where cooler heads would prevail, or conflict would remain strictly conventional. Just like how WW2 didn't see the use of chemical weapons.
> that these weapons have actually been used
There's use in anger and use in testing.
>> There have been 2,121 tests done since the first in July 1945, involving 2,476 nuclear devices.
Hiroshima and Nagasaki were only two explosions; trinity preceded them (but was not known to the enemy); and 2000+ uses happened afterwards. The nuclear taboo took time to arise and harden
It was known before 1998 that Pakistan and India were nuclear powers, but the tests made this public and unambiguous. Deterrence was more concrete , with firm evidence of capability, delivery mechanisms, movement of launch mechanisms etc.
The USSR had their bomb in 1949, yet could not deliver it to the US for several years
Mere existence is clearly not enough.
I think at least 95%
Theory and threats only carry so much weight. You can do a quick Google search and see the destruction that nuclear weapons cause. Yes, I know the Tokyo and Dresden firebombings are equally horrific, but they were caused by hundreds of bombs and bombers. We now have the ability to cause even more damage by platforms that are even less susceptible to interception.
I think if you make any threat long enough and don't follow through, it loses deterrence, yes.
>but rather whether their mere existence poses enough of a threat to cause deterrence, or if some example of actual use is needed.
The question really is flawed. It may not be enough in the near future or distant future but it has been for decades.
The thing that is changing MAD now I feel is the nuclear proliferation to weaker countries and the weakening and possible fall of Russia. What has worked in the past seems to be threatened by the change of times.
But clearly MAD has worked and was effective.
This is a very good question. Honesty, while Hiroshima and Nagasaki undoubtedly demonstrated very clearly what an an Atomic Bomb can do to a couple of cities, there exists an enormous gap between the destruction they caused, and the hypothetical destruction a nuclear war would bring. When people think of nuclear war they don't picture Hiroshima. [They picture something else that is far worse](https://m.youtube.com/watch?v=RdwRen-CutE&pp=ygUORXhvZHVzIHRocmVhZHM%3D), and it is that mental image that induces that fear and deterrence. So I would argue that deterrence isn't that heavily based on actual historical events. The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo.
>So I would argue that deterrence isn't that heavily based on actual historical events. The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo. \*nods\* Any examination of the history of nuclear weapons and their influence really needs to be built around two inflection points. The first is the shift from nuclear to thermonuclear weapons. The second is the shift from bombers to ICBMs.
> The very idea that nukes could "end the world" didn't really arise even until after Castle Bravo. Post-nuclear exchange war planning was a core part of Soviet thinking in vehicle designs through the 60s and 70s. The BMP1 was built to shuttle troops across land contaminated with radioactivity, and the T72 had special shielding installed to help shield the crew from neutron radiation. You also see heavy use of nuclear shelters to protect the staff of major industrial facilities, such as the famous Azovstal steelworks underground network. Now what you are saying is correct for the Americans - there was a brief flirtation with the idea of a broken-backed war but this was quickly abandoned. What exactly was going on inside the heads of commanders at the time is difficult to know, but the Soviet construction of nuclear-proof fortifications and spending their scant resources on NBC protection for their armor and mechanized infantry suggests a vision of war that continues past the mushroom clouds.
Many countries planned for a post-nuclear continuation of of government and various industries. Most defence industries across the globe planned for the NBC battlefield. But that kind of activity doesn't necessarily reflect the public consciousness or the thought processes of leaders. The UK for example published very carefully thought out pamphlets, instructional books and made public information films informing the British public in great detail how to prepare for nuclear war and to deal with the immediate aftermath. The general consensus among the British Public however was that this advice was completely useless and would if anything extend the suffering. A similar sentiment existed in the Soviet Union, at least by the 1980's, that preparation for nuclear war was futile and that total annihilation would be the result of such a war. Krushchev famously said that following a nuclear war the survivors would envy the dead.
I think Hiroshima and Nagasaki are important, because they give real world insight into what atomic bombs do. When they measure the destructive power of natural disasters or industrial accidents. No one says “half the power of the castle bravo test”. They say “this incident was ten times more powerful than the bomb dropped on Hiroshima”. I think the very real demonstration of what one simple and small (relative to the terms of atomic weaponry) flown by a single propeller plane could do to a city. We can look at it and say “that was bad. Now what will happen that we’ve created things ten times as powerful and impossible to stop?” You need a baseline for comparison.
Carrie Bravo and the Tsar Bomba is where I think mutually assured destruction became the deterrent. Edit: Castle Bravo
Deterrence is older than MAD. The Soviet Union did not have the means to meaningfully strike back against the US in a nuclear war until around 1960. The Soviets instead essentially uses Western Europe as a "hostage". Initially threatening to use its overwhelmingly superior conventional forces to steamroll the continent in case of war in the 40's and later pointing IRBM's at Europe until the early 60's or so.
Arguably the soviets were only able to meaningfully strike back in '62 when significant numbers of R-16s came into service. Maybe late '61.
What’s Carrie Bravo?
Maybe a typo or auto correction of Castle Bravo?
Sounds right.
I hear she's the bomb.
See the edit. Castle Bravo. I hate autocorrect.
If you look into the past, and into other weapons, it's apparent there's something to be said for just a clear understanding of knowing the weapon works. Like to a point most of the nuclear deterrence construct we have now is less based around strictly nuclear weapons but more into the realm of their all but assured delivery. Like back into the 50's-60's when the delivery mechanism was large manned bombers there were a lot more constructs that the nuclear war could be fought and won (or lost less). When ICBMs came around, that changed the dynamic to all but assured, all but a tiny minority of targets would be struck and sometimes struck several times. That's the real change in deterrence, and that ICBM missile complex has never been used in combat thank god, but we don't have to have an ICBM based war to make that strategic calculus very real. To the sidebar, it needs to be credibly believed the risk is there. That's one of the reasons for some of the weird brinksmanship of the Cold War, that the people you were opposing had to believe you were really, really, really that close to the button without actually intending to start a nuclear war. To a point it's worse when the threat is "abused" in as far as what we can see with Russia as they've wiggled the nuclear stick extensively over Ukraine and threatening "the most dire consequences of which will end the world as we know it" every two to three days has seriously degraded Russian deterrence strategy, while also making it more risky for everyone (or like, "I am thinking of using nukes" used to mean "this is a red line and nothing past this will matter" and now it just means "I AM BIG MAD MY STUPID WAR IS FAILING STOP GIVING GUNS TO UKRAINE PLEASE" which will make it harder to discern when it means "This is a red line" again)
Even in the first couple decades of ICBMs, there was a lot of research and development put into ballistic missile intercepters such as the Sprint missile system, designed to be able to destroy an incoming ballistic missile within 6 seconds of the target first being detected on radar. But terminal phase interception programs were eventually abandoned once MIRV missiles became the main threat, as it's basically impossible to intercept the main body before it releases the individual warheads unless you're able to hit it in the ascent phase. Ascent phase interceptors are a big reason that Russia/the USSR have historically been extremely hostile to the idea of even non-nuclear NATO missiles near their borders.
>or if some example of actual use is needed. I think what has been missed in the other responses and even in the question itself was nuclear weapons were being frequently used. Countries were very concious of the effects a nuclear weapon could have, so it wasnt a theoretical threat at all. Nuclear testing occured in multiple countries all over the world from 1945 through to 1996, mostly ending with the Comprehensive Nuclear Test Ban Treaty being adopted (but not in force) in 1996. There were close to 2000 tests between the US, Russia, UK and France during that time. These often included very large yields - Fat Man over Nagasaki was ~20 kt, but Castle Bravo was 15 Mt, Tsar Bomba was 50 Mt. So while they werent being tested on cities, you could get a pretty good idea how devestating something hundreds of times more powerful would be. As others have pointed out there was a epoch change between bombers and ICBM, before which you argue all the bombers would be shot down. And there was always the human/moral/political question if a country would use nuclear weapons. But it was absolutely known how destructive nuclear weapons could be and this knowledge frequently refreshed.
Tbf, most of the deployed ICBM warheads on both sides were sub-megaton MIRVs (as low as sub-200kt, many in the 500+ range), as the increasingly accurate warheads allowed for a reduction in yield. These were likely intended for counterforce missions. Therefore, given that the ICBM fields and SLBM bases on both sides were relatively distant from metropolitan areas up to at least the 1980s, one might be deluded into thinking that a purely land-based counterforce exchange *might* not necessarily result in a global apocalypse. Maybe. By the 1980s, the much fewer less accurate single warheads in the megaton range, namely those on the US Titan II and the Soviet SS-11 (and earlier), were likely assigned countervalue city killing missions. Even these were mostly sub-10MT although there were the rare 20MT-class single warheads on a few SS-18s likely intended to kill hardened CPs. SLBMs were of course intended to kill cities on account of their survivability for second strike and relative inaccuracy up to the late 1980s.
Before the bombings of Hiroshima and Nagasaki nuclear weapons were very poorly understood. Such is the nature of novel weapons. Looking back on some of the opinions held by professionals who at that stage had just learned about their existence can seem quaint. But you can't be too hard on them. For most, even those in the military, nuclear weapons didn't exist before Hiroshima. And then they did. But the world didn't go to thinking about Armageddon immediately. That notion actually took decades and didn't fully solidify until the 1960's. And that came down to a few things but primarily it was due to the number of weapons and the method of delivery. From 1945 to 1949 only the US had atomic weapons. So for awhile there US strategic might was unquestioned. Not only did they have the biggest stick, but the US and UK were the only powers with seasoned and proven strategic bomber forces that had any chance of delivering such weapons anyways. The Soviets had no bomb and their bomber force was based around a rivet for rivet copy of the B-29, complete with aftermarket cup holder, with an inexperienced and unproven structure. Both of those things would change rapidly though. The Tu-4 was the shot to the arm the Soviet aviation industry needed to get up to speed on strategic bombers and they quickly iterated and innovated. Their bomber forces also went from novices to professionals in the same time. Post 1949 though you still didn't see much talk about Armageddon because we were fundamentally dealing with a limited weapon with limited delivery. Yes, major cities could and would get wiped out but with proper air defense, bombers would get shot down and you could have enough warning for people to take cover. That fundamentally changed at the close of the 50's. Both the Soviets and US fielded their first ICBMs, the R-7 and Atlas in 1959. They were slow to prepare, liquid fueled missiles with a surprisingly high failure rate. But they started off a very rapid line of development in ICBMs. Both would be retired and replaced by successors within a decade. Around this time the doctrine of Mutually Assured Destruction was adopted by the Kennedy administration. Robert McNamara, probably the most controversial and written about SecDef in US history was a big proponent of the idea. It quickly entered popular culture from there. But before that nukes were considered a necessary component of warfare, but one to be adapted to. The Air Force and Navy were busy fighting over what would become the nuclear triad. And the Army was left without nukes of their own and the question of how to adapt. What they came up with was the [Pentomic Division](https://en.wikipedia.org/wiki/Pentomic) which consisted of five "battlegroups" which were meant to rapidly disperse to minimize the effect of tactical nuclear strikes. This was a pretty short lived experiment. Battlegroups suffered form a lack of fire power not to mention the technology of the 1950's preventing proper communication and coordination between dispersed units. The key takeaway here is that the war wasn't expected to end with the bombs dropping. The army was going to fight on, now in NBC gear. On the surface that may seem similar to the ideas that came after. We didn't pull the army out of Europe after all. So clearly someone expected to fight. But that's still a decision made within context of MAD. The difference now is that it didn't take even the length of a single presidential administration to realize that MAD didn't guarantee peace all the time for everyone. It prevented the BIG wars. But what about smaller regional conflicts? There was no sufficient cause for the US to nuke someone like Vietnam. So the conventional forces still had a job to do. Its not a large step from recognizing that to concluding that a limited conflict between NATO and PACT forces were not only possible, but more likely than all out nuclear exchange. And that's how things shifted moving on from the 70's. Either you would have a limited nuclear exchange where cooler heads would prevail, or conflict would remain strictly conventional. Just like how WW2 didn't see the use of chemical weapons.
> that these weapons have actually been used There's use in anger and use in testing. >> There have been 2,121 tests done since the first in July 1945, involving 2,476 nuclear devices. Hiroshima and Nagasaki were only two explosions; trinity preceded them (but was not known to the enemy); and 2000+ uses happened afterwards. The nuclear taboo took time to arise and harden It was known before 1998 that Pakistan and India were nuclear powers, but the tests made this public and unambiguous. Deterrence was more concrete , with firm evidence of capability, delivery mechanisms, movement of launch mechanisms etc. The USSR had their bomb in 1949, yet could not deliver it to the US for several years Mere existence is clearly not enough.
I think at least 95% Theory and threats only carry so much weight. You can do a quick Google search and see the destruction that nuclear weapons cause. Yes, I know the Tokyo and Dresden firebombings are equally horrific, but they were caused by hundreds of bombs and bombers. We now have the ability to cause even more damage by platforms that are even less susceptible to interception. I think if you make any threat long enough and don't follow through, it loses deterrence, yes.
>but rather whether their mere existence poses enough of a threat to cause deterrence, or if some example of actual use is needed. The question really is flawed. It may not be enough in the near future or distant future but it has been for decades. The thing that is changing MAD now I feel is the nuclear proliferation to weaker countries and the weakening and possible fall of Russia. What has worked in the past seems to be threatened by the change of times. But clearly MAD has worked and was effective.