You joke, but WWII was the first time that many Americans (especially soldiers) interacted with Japanese culture. A ton of American troops actually converted to Weeabism, and would carve images of their waifus onto their canteens and weapons etc. My grandfather was a cryptographer who worked on decoding some of the very first Hentai graphic novels. He even brought home an early 1940s body pillow which he named Chitoge Kirisak. She was the best grandmother I could’ve asked for when I was growing up.