Re: In today's news...
This is not Fallout. Once one nuclear missle gets launched you have a WarGames scenario where no one wins. Nuclear weapons are pretty much the ultimate bluff card. You will never see them used again but all the governments that can produce them need to if for no other reason than they can whip their dicks out and say they have them too.
In the height of the "cold war" USA and Russia had enough nukes to blow the entirety of the planet into a nuclear dead zone 2.5 times over. Yet no one was stupid enough to fire the first shot as it were. Even now as other countries catch up, they just realize having nuclear weapons means almost nothing.
You might be correct. On the other hand, I don't think it's prudent to claim, "you will never see them used again." Bear in mind that World War I, or the Great War as it was called at the time, was the result of carefully-crafted political alliances that were, in many cases, expertly-maintained by Otto von Bismarck, the "Iron Chancellor." When Von Bismarck was ultimately dismissed, the system slowly eroded. Eventually, a single assassination brought down the entire mess, resulting in a massive war that re-drew the political map of Europe and saw the rise of the Soviet Union. (Nationalism also played a part, but that's a whole different set of books. There are SO many books about World War I.)
It would be optimistic to believe that our leaders remember the lessons of the first World War, especially given the similarities in the current Nuclear Non-Proliferation regime. Over time, the number of states with nuclear weaponry is slowly increasing. Other states have nuclear backing to prevent them from needing to develop nuclear weaponry (for example, Japan and South Korea would likely have already developed nuclear weaponry for deterrence against North Korea and China, but are more-or-less covered under the US nuclear umbrella).
Another complication is when states openly declare situations in which they will launch nuclear attacks--many states with nuclear weapons have made declarations that their nuclear arsenal SHALL be used to defend their sovereignty. Historical evidence shows this to be an effective policy, as nobody invades a nuclear-armed state (many claim that Ukraine should never have surrendered their nuclear arsenal after the collapse of the Soviet Union, for this precise reason). But what happens when someone finally decides to test them on it? If the state fails to launch, they lose all credibility. If a nuclear-armed sponsor of a smaller state fails to protect them, they, too, lose credibility. Finally, with the ever-growing capabilities of terrorists, you have the possibility of nuclear arsenals that can launch without much fear of reprisal.
I'm oversimplifying, here, and I could go on for DAYS about this problem, so I'm going to cut it short here and sum up:
tl;dr The "bi-polar" situation with NATO and the Warsaw Pact was far more stable when you had the US President and the Soviet Premier as the only people who could authorize a nuclear launch. Now that we have more and more nuclear-armed countries, one could argue that the chances of a nuclear conflict have grown.
EDIT: Of course, we've got a significant advantage over our predecessors in the sixties--we know how much damage a nuclear war (and winter) can actually do, and no rational leader is under the illusion that one can "win" a nuclear conflict (as you pointed out). With that said, there are plenty of delusional people out there... and some of them are in charge of nuclear arsenals.
