But... that's stupid. Why would you kill everybody in NATO just because some of them are irradiated by an attack on someone else? It only makes sense to commit

But... that's stupid. Why would you kill everybody in NATO just because some of them are irradiated by an attack on someone else? It only makes sense to commit to nuclear warfare if they're actively doing the same, and even then it's mostly just out of spite because you're about to be gone. Letting Russia nuke europe and get away with it does have unforseeable consequences, but the consequences of all out nuclear war is 100% certain and maximally bad. You literally cannot do worse than this. You could instead, for instance, deploy the troops and just do a straight up invasion with the intent to destroy Russia entirely. Which maybe they do a nuclear response to. But maybe they don't. Because it's still the worst possible option and perhaps they'd like to instead just kill putin, accept a russia fragmentation into tiny vassal states. I'd also ask then, because you're saying "irradiating NATO citizens is the red line", whether you support killing everyone if there's a russian caused meltdown at the Zaporyzhzhia plant (sp).