You can have severe core damage without any nuclear reactions.

uh actually, i disagree, because in order for the event of a meltdown to establish any amount of core damage, or damage at all, you need to inflict fission. Otherwise literally nothing will happen, because thats how they generate heat, but i'm no nuclear physicist.

There aren’t “steam explosions” in physics.

yes? there are? Have you ever looked into 19th century steam technology? Do you understand how combustion explosions work? Yes technically it results from a chemical reaction of smokeless powder decaying, but unless you confine that reaction into a space, it just goes woosh. Once you confine it, and allow it to compress itself it can explode. You are literally just pedantically claiming that steam explosions aren't a specific subset of pressure explosions, the only reason that they are is because steam explosions are so easy to create, and so incredibly dangerous, that them existing in their own field is actually useful to current safety practices.

This is why properly regulated steam boilers can be used to provide steam to a steam engine to pull freight. But the second you get a low water level slosh event, and it sloshes back, the entire thing flashes immediately, blowing up the boiler, and if not immediately killing the crew, scalding them so badly they die shortly after because their lungs no longer function. I suppose you could argue that the burning of wood or coal is a chemical reaction here, but at the end of the day, it's the heat that turns water into steam, and steam that makes the power.

The steam was a pressure buildup that caused the incident resulting in an initial pressure explosion. The thing that “melted” the core of Chernobyl was the hydrogen exploding, hence a chemical explosion.

or maybe it was just the heat from the fuel and resulting runaway fission chain that caused everything to melt into a pile of nothingness? Nuclear fuel just sitting idly by, allowed to exist as is unmoderated (in significant enough capacity) will literally eat through concrete. That's why it's called corium.

Had it been a nuclear event that melted that core

it wouldn't have been, because that's not possible, and i never said that was the likely event. I just said that it was a steam explosion, which it was, and a potential hydrogen or secondary steam explosion, of which we aren't really sure on the source of.

Fucking with the literal power of atoms, in a mostly controlled environment, is the closest we’ve ever come to the Icarus myth.

idk man, maybe fucking castle bravo at bikini atoll? The one time we weren't sure whether or not a sustained nuclear fission event would ever stop because theoretically it could process the nitrogen in the air into more fuel, causing the entire earth to turn into a nuclear wasteland (it didn't btw) Nuclear fission as used to generate power is literally the safest possible use case of it. Modern reactor designs are literally incapable of having runaway thermal events. Research reactors use a specific blend of fuel TRISO to be specific, that has a specific formulation, that makes it physically incapable of having a thermal runaway.

I’m fairly certain that fusion power, should it ever come out of the theoretical stage, won’t be nearly as dangerous as fucking around with fission the way that we currently do.

i mean, fusion is likely to be less dangerous, i'll give you that. But not even that significantly, the main benefit to fusion is that it's the even more spicy nuclear bomb technology, and therefore, easier to exploit.