> For nuclear weapons it has become quite clear that even for small players, being in the race and having at least a few nukes is far more rational than having none. Ukraine found out the hard way that giving them up in exchange for promises of good behavior just sets you up for getting stabbed in the back.

I've heard a different perspective on this: Nuclear weapons need maintaining, and even maintaining them was probably beyond Ukraine's capability. Qaddafi gave up nuclear weapons after determining that they were just too expensive to be worth it; Iran damaged its economy to the tune of trillions of dollars trying to get nuclear weapons and so far failed; NK managed to get them but impoverished their nation to do it.