I was surprised to see that Sweden transferred its remaining plutonium to the United States around a decade ago. I would have assumed they’d have kept it around, just to keep their options open - it’s not like they were in an immediate post-USSR situation where unpaid nuclear scientists and unsecured cores were potentially up for sale and there’s a strong international interest in shutting that down. But then again, if Sweden did keep their options open, it’s not exactly the kind of thing they’d advertise - and the public story of the plutonium transfer is useful plausible deniability.
Japan, obviously, for a variety of reasons, doesn’t have nukes, but it seems pretty clear they could have an arsenal that’s functional as a deterrent in months, if not weeks. I wouldn’t be surprised if Sweden’s current doctrine is similar to that (though now being a formal member of NATO takes some pressure off that backup option).
> they could have an arsenal that’s functional as a deterrent in months, if not weeks
Japan is what's called a threshold/latent nuclear power. These are countries with the ability to build nuclear weapons immediately, but haven't turned the switch yet.
Taiwan, Iran, Canada, Germany, Netherlands, Brazil, Mexico, and South Korea are other threshold powers, and Saudi and the UAE are pressing for plutonium enrichment capabilities in the next few years as well.
Generally speaking, a country with a space program and a civilian fuel enrichment program can be safely assumed to be a latent nuclear power.
At the end of 2018 there was 9 tonnes of separated reactor-grade plutonium (about 66% fissile) stored domestically, plus a total of 36.6 t in the UK and France. That total of 45.6 t was a modest decrease from an estimated 47.3 t at the end of 2017.
Despite the name, "weapons grade plutonium" is not actually required to make a weapon. Japan could manufacture weapons of modest yield (comparable to those used against it in World War II) on a short timeline from reactor grade plutonium if it were willing to ignore the political reaction.
See this for a relatively brief technical explanation of using reactor-grade plutonium in weapons: "Reactor-Grade Plutonium Can be Used to Make Powerful and Reliable Nuclear Weapons" https://rlg.fas.org/980826-pu.htm
If you have a strong civilian nuclear power program, the ramp up time is minimal (weeks to months), as fast breeder reactors are a dual use technology.
If the country also has a domestic space program, you can safely assume they are also working on building IRBM capabilities
In Japan’s case, depending on what you mean they’ve already got IRBM (indeed, ICBM) capabilities. Their space industry has been building capable solid fuel boosters for a couple of decades.
I assume they haven’t actually tested a precision guided reentry vehicle, but that’s all they’re missing on the missile side.
I was originally gonna say that FBRs are in many places phased out (I think Japan's last one shut down in 2017) but if I'm reading right a BWR can work in a pinch, so there's -that-...
My guess with minimal knowledge in the field is, weeks if they have a shut down FBR plant, months if they have a decommed FBR Plant. I feel like building a new one to 'ramp up' would either require more time or perhaps multiple smaller reactor projects working in parallel might do the job...
In all honesty, it feels like everyone's arming for something big - from UAE all the way to the US and China, every country is in the process of buying startups and firms working on dual use technology.
Every country seems to have some sort of a 5-10 year roadmap to modernize defense technology and logistics by 2035, yet I never saw this level of concentrated effort globally after 1989.
That said, I sincerely hope my prediction is just paranoia and that I'm wrong.
It's UAE and Saudi's deal flow that got me worried recently. I'm seeing those guys everywhere in the defense tech space now, and if Saudi and UAE are stockpiling, then every other semi-competent regional power is as well.
Saudi Arabia might already have access to nuclear weapons earmarked by Pakistan, as part of an agreement, when Saudi Arabia helped fund Pakistan's nuclear program.
My limited understanding was that one of the core technologies needed to build a nuclear bomb is the explosion lens that uses conventional explosives to put pressure on the nuclear material. And this technology is not something that is involved in space program or using nuclear power peacefully.
Nothing has to push them. These countries want to go nuclear. The only thing preventing them is the threat of american intervention. Japan and South Korea had secret nuclear programs that we put a stop to. Canada, Brazil and Mexico will never be allowed to own nukes. No nation in the western hemisphere will allowed to own nukes outside the US. As for germany and the netherlands, we'd sanction and isolate them if they ever developed nukes. They could have nukes, but their economy would be in shambles like north korea. If taiwan went nuclear then it would be the end of taiwan and both the US and china would take them out.
That makes sense, so I guess once Ukraine loses, it'll make more sense for them to push the button and get ready. Better to be hungry and free than ending up in Siberia.
There are many legends about fissile material, or even “bomb kits” hidden away in some of Sweden’s many hollow mountains.
According to Wilhelm Agrell’s book “Svenska förintelsevapen”, the foundation for one such legend is as follows: There was a chunk of plutonium in a lab somewhere, acquired from the UK, I think. When the nuke program was ramped down, it was decided that this chunk should be transferred to a certain laboratory in Norway. However, getting the bureaucratic stars aligned to do this “by the book” turned out to be a major headache, to the point that some exasperated manager eventually packed the stuff in his briefcase, drove to Norway in his own car and handed it over personally, thus breaking every rule in the book and a few not yet written, but at least getting rid of the cumbersome thing from his lab!
Japan, obviously, for a variety of reasons, doesn’t have nukes, but it seems pretty clear they could have an arsenal that’s functional as a deterrent in months, if not weeks. I wouldn’t be surprised if Sweden’s current doctrine is similar to that (though now being a formal member of NATO takes some pressure off that backup option).