You just made the point that if Ukraine kept it's Nukes, the EXACT same principal applies for deterrence, thank you
ps: Not sure if it really matters what kills you as a Ukrainian, a Russian FAE, or a Russian Nuke, Dead is Dead
The difference comes in the fact Ukraine had nukes at one time, they don't have FAE's or the ability to hit a Russian city with one..
Lesson:
Don't give up your weapons on the promise of protection from a Politician