The Iranian-USA conflict resparked an interesting conversation - what kinds of nuclear defense does the USA have in secret? I'm no expert in secret military tech by any means so all of my opinions are my speculation, but I have to imagine that the US has some method of shooting down nuclear missiles with high accuracy, maybe 90%. If we look at the technology we definitely have the methods of shooting a nuclear missle mid-air (automated, super accurate, heavy turrets). We would just need to build those. The question is whether we have a reliable enough method of getting position data for the nuclear missiles, and I think radar + satellite imagery wouldn't be enough to live without fear. What other ways could we detect a nuclear missiles exact position?