No one has disagreed with you on this.
And, once again, no one is disagreeing with you. IF you have a legal prescription, you are not breaking your State's law by smoking. Where everyone is disagreeing with you is that your right to smoke does not trump the employer's right to not hire you--or fire you. They DO have that right...and courts will uphold it time and again. And, of course, anyone who maintains Federal employment recognizes Federal law...not State laws.
Common sense is not up for debate here. What is being discussed is whether your legally-obtained prescription entitles you to smoke anywhere, anytime, without any consequences. It's not common sense, but rather the LAW that tells us this is NOT the case....you cannot smoke anytime, anywhere, without consequences. There are....and you are required to accept that if you accept the employment.
You seem to be operating under the misconception that only nurses would be accountable for being impaired while at work, and that their legal use of certain prescription drugs could negatively impact other people. I'm pretty sure physicians would have the same liability, and accountability; no witch hunt in place for nurses alone. Same would be true of school bus drivers, long-haul truckers, and the list goes on. Nurses are not held to an exclusive rank of being restricted in their drug habits.
Can only speak for myself, but online discussion isn't really exhausting....a 14 hour shift, well, THAT'S exhausting