Assuming no technology is absolutely perfect, absolutely risk free, what if the the nuclear warhead detonate accidentally ? Wouldn't be less risky that, for instance, a russian nuclear warhead accidentally detonate in a russian military base in Siberia rather than in the russian consulate in the center of NYC ?
One of the factors to consider, that contrasts with old-fashioned hostage exchanges as described, is that you would never allow your nation's leaders to visit any city that you knew had such an arrangement. Not as a group, and probably not individually. You could never justify doing this kind of agreement for Washington DC or Beijing or Moscow, in the way that you can justify, "We both have missiles that can hit anywhere, including your capital city." The traditional approach is to make yourself vulnerable enough to credibly signal unwillingness to betray one another, but only enough that there is still a price at which you would make the sacrifice.
Also, consider that compared to the MAD strategy of having launchable missiles, this strategy selectively disincentivizes people from wanting to move to whatever cities were the subject of such agreements, which were probably your most productive and important cities.
There's are real concerns, but I feel like we are only formalizing the status quo.
Throughout the Cold War, it would have been fairly easy to kill the other sides leader, especially if you are willing to use a nuke. I still thank that is true. The president's travel schedule is public, and its not like he's always within 15 minutes of a nuclear bunker. The reason countries don't assassinate each other's heads of state is not because they are unable to.
If you live in Manhattan or Washington DC today, you basically can assume you will be nuked first, yet people live their lives. Granted people could behave differently under this scenario for non-logical reasons.
If you live in Manhattan or Washington DC today, you basically can assume you will be nuked first, yet people live their lives. Granted people could behave differently under this scenario for non-logical reasons.
My understanding is that in the Cold War, a basic MAD assumption was that if anyone were going to launch a first strike, they'd try to do so with overwhelming force sufficient to prevent a second strike, hitting everything at once.
If you can strike in a way that prevents retaliation that would, by definition, not be mutually assured destruction. Your understanding is also wrong, at least for most of the cold war. Nuclear submarines make it impossible to strike so hard they can't fire back, and they have been around since 1960. People in the cold war were very much afraid of living in a potential target area, but life went on.
If you can strike in a way that prevents retaliation that would, by definition, not be mutually assured destruction.
Correct, which is in part why so much effort went into developing credible second strike capabilities, building up all parts of the nuclear triad, and closing the supposed missile gap. Because both the US and USSR had sufficiently credible second strike capabilities, it made a first strike much less strategically attractive and reduced the likelihood of one occurring. I'm not sure how your comment disagrees with mine? I see them as two sides of the same coin.
Maybe instead of threatening a city it can just threaten a country's top leaders, e.g. they have to wear bombs.
I thought about something like this (A nuke near the White House) but quickly realized the bomb would have to travel with them. There's just no way to make it secure enough with the travel schedules such people have, and the adversary's inspectors would have to follow them around to enforce it so there's no privacy either. Not to mention all the world leaders occasionally gather in one place, which raises the danger even more.
Given you could use a conventional, small explosive, that makes it easier, but my guess is it still does not work. There are at least two big issues:
Maybe it's a ring that explodes if cut? I'm not saying I can prove it'll work, just that there might be some way or another to target the leaders rather than random civilians in a city (which the leaders might not care about).
If a country wanted to perform a nuclear first strike, launching a missile might be the wrong way to do it.
What if instead, the attacker smuggled the bomb in and remotely detonated it? A nuclear warhead can be as small as a trashcan[1], and they are undetectable outside a very close range[2] (10 meters without shielding). What could stop a capable attacker from smuggling a warhead into a Manhattan safehouse? What if one is there right now? How would we know? Nukes designed for smuggling have been proposed and developed.
What if this was done intentionally by treaty?
It seems crazy, but we already accept in principle that all nuclear powers are capable of destroying each other. Granting an adversary a small base in a major city(s) to stage a nuclear warhead doesn't change that. It would only formalize that capacity.
Intentionally making yourselves vulnerable to each other is actually a time-tested diplomatic tool. Today, a hostage exchange means we get our guys back and you get your guys back. In the past, it meant we give you some of our guys and you give us some of your guys. That way, each side has a reason not to attack the other. This was an integral part of diplomacy for much of human history.
Hypothetically, such an agreement could already exist and we wouldn't know. If our government negotiated a "bomb swap", it might be highly confidential. "Hey guys, I let China put a nuke in Manhattan" seems like a bad PR strategy. (I think the possibility these agreements already exist is very slim, but I have no concrete evidence.)
What could the advantages be?
Nuclear powers are entering a new arms race for the next generation of MAD. The development of highly capable missile defense systems and hypersonic missiles forces countries into a loop of developing ever better versions of these technologies[3]. In addition to being expensive[4], this also creates uncertainty[5]. "Could X missile be stopped by defense system Y?" Uncertainty in the context of MAD is a bad thing.
This dynamic also has the potential to be upended by Artificial Superintelligence, which could give one country an overwhelming advantage in both missile attack and defense[6]. It is easy to imagine this making nuclear powers who are left behind uncomfortable, even reckless.
A bomb swap could put MAD on a more solid and predictable footing as we enter a period of increasing unpredictability, and save everyone a lot of money.
What concerns are there?
Aside from it being politically toxic, there could be serious concerns around chain of command, terrorism, and accidental detonation. What would the exact mechanism be for triggering these bombs, and how could it go wrong?
Given these "nuclear embassies" would be within the adversary's territory, the potential to cut or jam signals to the controlling country exists. They would need to act like nuclear subs, capable of independent retaliation. This introduces concerns around unauthorized use, however the solutions that could be applied here would be no worse than those already applied in nuclear subs.
Assuming nuclear embassies are manned by humans, they would either be suicide missions or require a deep bunker for the operators to trigger the bomb from inside. This seems feasible. The Cheyenne Mountain Complex is built under 2000 feet of rock and designed to withstand a 30-megaton bomb within 1.2 miles (The largest nuke ever was 50-megatons[7]). This is a major facility, comprising 15 three-story buildings. A minimal bunker could be constructed at comparable or greater depths. Many mineshafts go far deeper[8]. Nor does the bomb need to be detonated directly there. Missile defense would not make a difference if the warhead is just being catapulted from one end of Manhattan to the other.
Perhaps the biggest concern is unintentional detonation. If a nuclear warhead unintentionally detonates in a submarine or a silo in a cornfield, the consequences would be small compared to a major city. There is also the diplomatic hazard. Such an incident might be interpreted as an attack, and start a full-scale nuclear war. Worryingly, our track record of unintentional detonation as a species, while technically spotless, is full of close calls. It is worth noting however that almost every incident is a result of a problem with the bomb delivery system, like an airplane crash or missile explosion. These systems would be comparatively inert, hopefully meaning less opportunity for things to go wrong. Still, the host country would probably require routine inspections and the highest safety standards enforced.
There is also a concern about the host country "rushing" nuclear embassies in the event of a war to disable them before they can be used. A natural response to this would be detonation. Therefore, a misinterpreted rush could present a significant danger. Strict protocols would be required for entering.
Finally, these bombs would be an attractive target for terrorists. As a result, these sites must be heavily guarded by the host country.
I am not endorsing this strategy.
There are probably many factors I have not considered, and the downsides may outweigh the upsides. It's also possible we don't want to preserve MAD, or we only want to preserve it with certain countries. (No reason to let North Korea make such a deal.) I still think this is an interesting, and to my knowledge, novel strategy for diplomacy.
https://en.m.wikipedia.org/wiki/W80_(nuclear_warhead)
https://scienceandglobalsecurity.org/archive/1990/01/detecting_nuclear_warheads.html#:~:text=In%20the%20absence%20of%20shielding,distance%20of%20tens%20of%20meters.
https://www.defense.gov/News/News-Stories/Article/article/3391322/general-says-countering-hypersonic-weapons-is-imperative/
https://www.cbo.gov/publication/58924#:~:text=about%20Mach%209.-,DoD's%20Current%20Hypersonic%20Missile%20Programs,programs%20to%20develop%20hypersonic%20missiles.
https://www.ucs.org/resources/how-does-missile-defense-work#:~:text=GMD%20vs%20Aegis%20vs%20Patriot%20vs%20THAAD&text=The%20process%20begins%20with%20infrared,system%20relies%20solely%20on%20collision).
https://situational-awareness.ai/the-free-world-must-prevail/
https://en.wikipedia.org/wiki/Tsar_Bomba
https://www.miningmagazine.com/management/news/1263149/deepest-shaft-us-complete