Let's face it, this is a red-scare and nuclear preparedness propaganda flick, not even thinly disguised. The Russians knock an alien missile our way, and our valient defense network responds to save NYC in a matter of hours. The film showcases our missile detection/response network and alligiance with Canada, as well as the "precautions" to safeguard citizens with fallout shelters.
My dad was in the military as part of the early detection group, and I was delighted to see one of the radar planes he flew on shown in this film!! I wish I could have seen this film back in the 60s when he was still at that task. It was 10 years ago I finally got to see one of those planes in an aircraft boneyard.
So the whole movie was a treat for me, as I remember all the bomb drills and the constant talk of attack and nuclear annihilation. What a gem!