Apparently one of Frank Herbert's many obscure inspirations was the book "The Sexual Cycle of Human Warfare" by N.I.M. Walter which argues that war is like a civilizational-level collective orgasm.
In this case a quick search didn't reveal it, but Google books has a scanned copy which you can use snippet view on so I wouldn't be surprised if there's a copy somewhere on archive.org
edit: hackernews regular gwern appears to have a digital copy of the book.