It would be too great a cost. Russian people are not the enemy. The ruling class is.What's the etiquette for nukes? A nice little shot across the bow as a chivalrous warning in some sparely populated oblast. Or would the West have to simply "empty the clip" on Russia? Dead Hand propaganda aside, I tend to think there would be tremendous advantage in making an overwhelming dawn raid style first strike. Even if there is somehow just enough of the good ol' Apollo 11 style genius left in the US of A, along with key allies, could the level of destruction ever be justified, even if the execution avoided MAD?