Maybe the link between
Red Dawn and conservative doctrine is less clear today, but at the time it came out, it was pretty much an illustration of the worst-case scenario that Reagan and his ilk warned against and used to justify a lot of their policies: "This is what will happen if we don't toughen the military/build more nukes/cut social programs to pay for the above/etc." So taken as a cautionary tale, it aligned pretty well with the narrative of 1980s American conservatives.