On that note: Trumps golden dome has the chance to end this paradigm, since with it the US can now Nuke countries that it likes without direct payback (which is probably the point of the whole thing in the first place).
The problem with that is that it changes the incentive on nukes into using them in more concealed, non-attributable ways, like smuggling a suitcase nuke into Manhatten and have everybody wonder which nations or terrorist organization it was.
And it's more than the fantasy of a madman??
1) EMP strike. The device is a big h-bomb peacefully sitting in orbit, pretending to be something else. Push the button and basically everything to the horizon (which is a very long ways) gets fried. Some of the hardened military stuff might survive, but the country is gone. The survivalists might hang on for a while, but they can't rebuild.
2) Salvage fuse. You put a proximity sensor on the missile that detonates it if something comes sufficiently close. All the antennas and missile seekers looking at the area are dazzled if not destroyed. The defenses have a very hard time engaging the next missile. The next missile doesn't need to be looking at anything, it doesn't get fried.
3) Suppose it "works"?? Nope, the reality of missile defense is that you spend more on the interceptors than your enemy spent on the missiles. Iron Dome is last I knew $50k/shot. And note what happened in the aftermath of 10/7--Hamas bled the launchers dry with rockets that were at least an order of magnitude cheaper. Last I knew Iron Beam was only test-deployed (shooting at real inbounds but not considered fully operational) and even it can be swamped. And it's only a short range defense. And it takes dwell time--salvage fuse becomes an issue even though it's an energy weapon. Point defense, yes. Country defense, no.
Nuclear explosions leave traces that you can link to a specific country's nuclear program. Check "nuclear fingerprinting".
Any such tech will be highly destabilizing for the decade or two it takes to build and deploy.