I doubt China would just blow up a bunch of American aircraft carriers with a nuclear weapon, unless they were under existential threat. China would be severely

I doubt China would just blow up a bunch of American aircraft carriers with a nuclear weapon, unless they were under existential threat. China would be severely disadvantaged in a nuclear conflict I would have thought, and would try not to go there under any circumstances. North Korea even moreso. As such, non-nuclear approaches remain relevant.