

“Ever since nuclear-armed intercontinental-range missiles were deployed in the 1950s, the United States (and its potential adversaries) have been vulnerable to nuclear attack. This is very unnerving, and has caused our leaders to search for some kind of technical fix that would change this situation by making it possible for us to defend ourselves against such an attack. Fixing this situation is also very appealing to the public. As a consequence, new systems for defending against ICBMs have been proposed again and again, and about half a dozen have been built, costing large amounts of money, in the hope that a technical fix could be found that would make us safe. But none of these efforts have been successful, because the difficulty of defending against nuclear-armed ICBMs is so great.”
https://www.404media.co/scientists-explain-why-trumps-175-billion-golden-dome-is-a-fantasy/
Actually, I would say you sound more like the cave person in this discussion. “Sounds great, let’s do it” is not a reasoned nor analytical approach.
Is it possible to build it? Maybe. Perhaps even probably. Does it make sense to build it? That’s a much better question. Overwhelmingly, the scientific response, since Regan first proposed it, has been “No”.
The biggest problem is the “plus 1” problem. Say you have an array of 100 killer satellites, each with an intercepting missile. Well an adversary can see all 100 satellites, and simply has to launch 101 ICBMs — or 100 cheap “dummy” missiles and 1 real one. It only takes 1 getting through to vaporize an entire city. The killer satellites would likely be a billion dollars or more each, and they are rendered completely useless by a relatively inexpensive fake missile — mostly costing just the price of fuel. You can’t take the chance that any launched missiles are not real, so you must intercept all of them. No matter how many killer satellites you have, it will be trivial to swamp them with cheap fakes and have a few real ones hidden in the volley. Inevitably some of the real ones will get through.
There’s another huge problem someone else alluded to — such a satellite system would be trivial to completely destroy before even launching any ICBMs. The most likely deployment would be LEO (low earth orbit). Destroying any satellite (either from another satellite or from a ground based launch) would send debris out in every direction. That debris would then collide with other satellites, starting a chain reaction that would likely take out most of the satellites in LEO trajectories around earth (including things like starlink, etc).
There are tonnes of other problems with Star Wars/Golden Dome/Iron Dome but just these 2, I think, make it a complete non-starter with our current technology.
I get how seductive the idea is. And one day, perhaps with high energy lasers and technology we clearly are decades away from today, then it might be possible. Spending 100+ BILLION dollars on this today is simple a pipe dream — or the greatest scam in history (more likely).