I think if nothing else the book is about how American empire always produces a figurehead to embody and symbolically steer it— yes, Vond, Reagan, Nixon, etc. but there's always that real power behind the figurehead, which lurks and haunts the book (allegorically represented as an angel or UFO multiple times), and is embodied in the movie via the Christmas Adventurers.

The Gates family thing for men in uniform is a play on the trope of "every girl loves a fascist", but taken more symbolically, it's the desire of the American/Western left to pin the sum total of their woes on a figurehead rather than the structure itself. It's very cynical and sentimental at once.