It's unlikely that they will engage nuclear weapon if the west intervene in Ukraine.
Go back to 1986, and imagine what the Soviet response would be if NATO would have breached the Iron Courtain and would have fighter planes and tanks in Kiev. This is what we're dealing with here.
"A shame your tanks exploded. Perhaps their car warranty expired?"
For all we know, this is already happening.
When we talk about the risk of a nuclear escalation we talk about the risk of this or that country launching nuclear armed missiles at an other country.
How would the posession of nuclear reactors factor into that?
If Russian will capture nuclear reactor, they can convert it to nuclear landmine, because reactor uses enriched Uranium, to create equivalent of 10k Chornobyl's.
Ukraine has know-how and nuclear materials (Plutonium) to create nuclear weapons at will. The only thing that stopped us is USA, Britain, France, and Germany, which used Budapest memorandum as leverage against Ukraine to prevent that.
Now, maybe if Russia captures a reactor they could send a scientist down to repurpose its parts to make an improvised nuke, but if that's the goal, what would be the point? It's not like Russia doesn't have nukes already.
Just having plutonium and knowledge is not enough to build a nuclear weapon. No country has ever developed nukes while its main territory was being invaded. For one, even if you can build a device, you'd need to test it at least once. What would you do if you had nukes and you detected that the non-nuclear-capable country you're invading has just run a nuclear test?
The point is to use the nuclear reactor like a nuclear landmine, to blow up at retreat, to do maximum amount of damage. It's called «scorched earth tactics».
Ukraine, as part of USSR, developed nukes decades ago. Ukraine is the fist post-nuclear country in the world.
Nuclear reactors can't produce nuclear explosions, for the reasons I said previously. Even the Chernobyl incident wasn't a nuclear explosion, it was a steam explosion. It's no more possible to turn a nuclear reactor into a nuclear bomb, than to turn a gas generator into a molotov cocktail. I don't know where you heard this absurd notion of a "nuclear landmine", but anyone who talks about exploding nuclear reactors is just spreading sensationalism.
Yes, Ukraine had nuclear weapons. Had. It has since dismantled all of them and doesn't have the infrastructure to make new ones. As such, it would have to develop them again. They have to build the machines to build the weapons and then they have to test the weapons to make sure the machines are building them correctly. Then they need some delivery system, which is a problem entirely separate from merely making a device that can produce a nuclear explosion. Good luck doing all that while infrastructure is disrupted by an invasion.
2 weeks ago it was "unlikely" Russia launches a full scale war on Ukraine. Putin is crazy and will use nukes if he deems it necessary.
We have a lot to hate about putting,but it comes from his inaction to solve a genocide on his very border. Instead, he only acted when russia was threatened. Sounds logical to me.