I grew up not too far from a major military base. My dad explained to use kids that if there were a nuclear war, we had nothing to worry about, as the military base would be targeted and we would instantly evaporate in the initial blast. True to his word, he never did any prep for nuclear war.
Later in life, I watched as Chernobyl, the greatest nuclear disaster in history, unfolded. We were told that millions of people were going to die early due to cancer or whatever. Shows like The Simpsons didn't help, propagating the idea that nuclear power plants caused mutations and such. In the end -- only a handful of people suffered any ill effects, and those were the people directly exposed to radiation from the exposed core. No increased cases of cancer, no shorter lifespan.
After several decades of recovery, today Hiroshima and Nagasaki are beautiful cities. The fears we had about fallout and what not simply never materialized. Now we know that people in the immediate blast area get killed, some people on the edge get irradiated beyond hope of recovery, but everyone else has a chance at living a normal life thereafter.
Nuclear weapons themselves are a weapon from a time when war was general, when you tried to destroy entire armies and population centers in one go. Today, war doesn't fight like that. Perhaps it is the threat of nuclear war, or perhaps it is the fact that once you glass an area, you rule over sand. Perhaps it is the fact that at the end of the day, you have to send boots on the ground to control an area. Nuclear weapons do not replace military patrols.
On a side note -- nuclear weapons are not easy to make. In fact, I remember reading the reports from the North Korea "hydrogen bombs". The data suggested that they no only failed to initiate the fusion process, but they also failed to get the fission process working. In the end they built a dirty bomb. They'd get more bang for the buck if they just packed the hole with dynamite and lit the fuse.
I totally doubt that any countries outside of the US and Russia even have working nukes. Sure, India and Pakistan claim to have nukes, along with several other countries, but maintaining those nukes so that they will actually explode is extraordinarily difficult. Making nukes in the first place -- I am convinced if you gather all the scientific literature in the entire world on nuclear material you would fail. I cannot imagine nuclear scientists who actually understand how these things work publishing the right numbers or even the right theories. I wouldn't publish that kind of data in the open if I had access to it, even if you put a gun to my head.
If you wanted to build a nuke, you'd have to run through the entire Manhattan project on your own, having your scientists discover the actual mechanisms that govern how nuclear interactions work, detailing the numbers to a fine enough resolution that you could reach critical mass. And after all that, which I doubt any country could accomplish, possibly not even the United States given the "science" culture of today, you'd have the nukes we made in the 1940s. Barely worth it, since you can just pack more TNT in a bigger box and get a bigger boom.
Do I care whether or not Iran has nukes? Absolutely not. In fact, I wouldn't care if everyone had nukes. I'd be more worried about supersonic missiles and machine guns than nukes.
