Back in the early days of the Cold War all us little kids were taught to dive under our school desks to shield ourselves from an incoming Commie nuclear attack. (I'm still questioning the wisdom of letting little kids crawl all over lead-lined desks all day, but that's a topic for later.) I'm sure this would have worked great so long as the Rooskies attacked between the hours of 8 am and 3:15 pm, and respected recess, lunch times, and summer vacations.
Things are different today. First, the Russians are likely not our main existential threat. Russia's Vladimir Putin no doubt remembers the concept of "Mutually Assured Destruction" or MAD, which meant both sides knew if they launched an attack on the other, they themselves would be vaporized in retaliation about five minutes later. Putin may be an evil bully, but he isn't stupid. He knows he can get what he wants via something virtually untraceable back to the Motherland: cyber warfare.
Nor is China a likely existential threat to America. Their version of modern Communism....let's call it Communism Lite....likes making a profit, and we're their biggest customer. We need to keep each other happy. Neither of us has much to gain, but a tremendous amount to lose, by nuking the other.
Iran....they could be, likely WILL be an existential threat to us sooner rather than later. Our nuclear deal with them of a few years ago was, in retrospect, a joke. They're probably still laughing over how gullible we were. Their radical Islamic leadership would probably be willing to write off a few million of their own people in exchange for poking an infidel in the eye. The good news for us here in 'Merica is that Israel is geographically much closer and has vastly more to lose than we do, so before Iran can truly threaten us, Israel will....umm...."handle it". *wink*
North Korea, however, is another matter. Their people might be perpetually on the verge of starvation, but Kim Jong Un still lavishes money on his nuclear program. I doubt he's concerned about a few million of his people being wiped out in a nuclear retaliatory strike....the MAD concept probably means nothing to him.
Prez Trump thinks China can control them, but I have my doubts. Even if China cuts N Korea off today, it's too late. That train has already left the station. China is probably thinking if they
piss him off anger Kim Jong Un, he might someday lob a few nukes their direction, too, so they're tippy-toeing their way around "The Little Fat One" as well. For the time being I'm not particularly worried about Crazy Kim hitting my zip code with an ICBM....he'd probably have a tough time even hitting Texas! As a geopolitical junkie, I'll admit this one is going to be "interesting" to watch play out.
Have I missed anybody? Is there anyone else you can think of that might have a nuke or two set aside with our name on it?
And most importantly, now that you're an adult, do you have a Big Boy or Big Girl desk you can fit under? ;)