Didn't the gradual advent of precision guided munitions remove the point of having air-launched tactical nuclear weapons? Assisted by deterrence now being applied on smaller scales by moves to allow land and submarine launched ballistic missiles to adopt a sub-strategic role?
Is the idea of a nuclear-armed F35A not just a carry over from an early 1980s picture of a F4/F16/Buccanneer-led slow-motion approach to armageddon in the Fulda Gap?
An opponent who's earned themselves a nuclear strike is quite possibly in possession of a sufficiently integrated air defense system to make the reliable arrival of weapons from any sort of F35 at the target unlikely.
In this context, the USMC's proposed use of F35Bs against a colonial coast seems perhaps to be rather more realistic.