Imagine a group of kids in a classroom. Don't ask me where the teacher is man, I don't believe in Teacher. If you want, there's a substitute teacher who spends all his time reading romance novels instead of keeping order. If kids misbehave he says "Hey. You kids mess around too much."
Anyway, one of the kids, Billy, is US and this kid can really fart. That's right, his farts stink and he can fart on command (it involves eating the right beans the day before or something like that), and one time he farted on a kid during an argument and that kid was so embarrassed he shut up right away. Some of the other kids have learned to fart on command too, but mostly, those are friends of Billy. Eventually though the kids realize that if everyone has a fart war it really really stinks up the place for everyone. Plus the girls think it is stupid. So they decide not to fart at each other anymore. If anybody farts at anybody else, everybody farts on him. They won't try to stop people from eating beans; that would require bean inspections and that's lame.
Imagine then what happens if the kids who don't like Billy decide to mess with Billy about it. One of them makes a farting sound when Billy isn't looking but when Billy wheels around, it becomes apparent the kid is just making fart noises with his armpit. Some of the kids are getting sick of the fart vigilance and Billy looks really silly prophecying about fart doom all the time. At a different point, of two kids that are fighting, one of them develops fart technology. People begin to wonder whether the age of farting will come again to the classroom. Kids are talking about what would happen in the ensuing "fart winter." Okay, no they don't, but one of the kids is constantly going "if you guys don't give me candy, I'm totally gonna eat some beans tonight." Another of the kids is like "No, I do not fart. I eat beans all the time but my digestive system breaks them down in such a way as it does not make me fart. My intentions are peaceful and fartless."
Well, I'll tell you how this thing is going to break down. Kids from the Axis of Evil are going to be faking like they're farting and Billy'll get mad and talk to them and sniff the air and try to figure out if people are really farting. And eventually, in all the noise some kids going to fart and its going to stink. And every one of those little Rogue Kids is going to say "It wasn't me." What does Billy do then? Fart on every one of them? Beat them all up?
And then little Billy and the rest of the gang are either going to have to get used to the smell of farts, because the alternatives are now "fart wars" and "the international terror fart game."
There's a terrible flaw in your strategy. You are complaining about us pushing people around. For me, that is an accepted cost. It's annoying and to the people being pushed around, it doesn't seem very fair.
Your solution, to prevent pushing people around is to allow nations which aren't very safe, some of whom support terror directly in an age of terrorism, to develop weapons capable of killing thousands of people. The way we'll keep them from doing it is to nuke them back.
Your accepted cost is that there's a chance that thousands upon thousands of people will die. You mitigate this risk with a threat of force.
Threat of force comes with all sorts of issues though. First off, terror can be anonymous. A nuke goes off in NY. Who do you nuke Unordained? Will you comb the radiation soaked remains of this part of NY for clues as to which country sold it to whom who set it off? Even if you find out, can't they say "it was some jerk who stole our weapons and sold them. We've caught him and killed him." Even if we had a really nice nuclear missile defense system, it wouldn't stop a nuke that wasn't a missile that was parked in somewhere awful.
Secondly, a threat of force can be overcome if the threat is "overworked" as they say in chess (a queen protecting three things may only be able to actually protect one if you call their bluff and accept one threat). Fortunately, we have no small number of nukes. As long as we can launch a very large number of them in the time it takes one of them to hit, we can nuke as many people as try to ally against us.
Then again, with enough threats against us, we'll be so dead that it won't matter whether we kill them back.
It seems to me that it also needs to be considered that there are people out there who aren't as afraid to die as we are. People that don't mind getting aboard a plane and driving it into a building. If such people got their hands on a nuke, do you think the threat of force would matter to them? They'll call your bluff.
This strategy is a nice backup strategy. For now, I don't mind pushing people around. People will whine and cry about what right we have, as the only country on earth to have used the weapon to prevent others from doing so. But it really doesn't matter. We have the power to do so. And the cost of not doing so could be pretty high.
These days, being aggressive against another country doesn't require an open declaration of war. It can come in the form of trade embargoes or heavy tariffs, terrorists, and other things which cannot be strongly linked back to the country which set them in motion.
The last thing this world needs is a fart war. The only thing to do is keep people who don't already have bean technology from acquiring it. And if they do acquire it, make them really sorry they did with constant inspection and such.