When Russia promised Ukraine that Russia would allow sovereignty if Ukraine give up those 1700 nuclear warheads, that was when Russia was too weak to forcibly retake those warheads, what if NATO offered membership then? That would add 1700 nuclear warheads to NATO arsenal. But not exactly under NATO control because they were legally Russia's. Not only that, Ukraine did not have a reputation of being a stable power, let alone a nuclear weapons state, like the UK or France. Still, I wonder what would have been the responses if NATO made that offer.