Rather unlike today, during World War II most people in the American entertainment industry were actually pro-American patriots — even a lot of hardcore left-wingers like Theodor Geisel. Perhaps that wasn't always 100% a good thing, but there it was.
Even a number of popular cartoons were used as vehicles for pro-war patriotic propaganda. Warner Brothers cartoons were noteworthy in that respect, with Bugs Bunny whipping Axis ass, as in "Tokio Jokio." South Park was specifically paying homage to these patriotic cartoons in their own classic immediate response to 9/11, "Osama Bin Laden Has Farty Pants." These vintage cartoons are a useful direct window into how the popular culture of the time looked at the situation, certainly much different than today. Try to imagine Matt Groening letting the Simpsons sell war bonds. We'd be fairly well screwed if we were dependent on Homer Simpson to save the land.
Being a mighty sailing man, of course Popeye got recruited for some of the WWII propaganda fun, as when he single-handedly dispatched a sub full of Asian enemies in the infamous "You're a Sap, Mr Jap."
I was struck today, however, by a 1943 Popeye short, "Seein' Red, White and Blue," especially because it pokes at my own hot buttons and ambivalence. The basic plot involved Bluto trying to get out of the draft, with Popeye representing for the draft board. This gets at something of a point of tension to me, as I've become much more hawkish in my thinking in this post-9/11 era of jihad.
I tend to favor killing dangerous enemies, but I'm still the libertarian that I've always been, and I still reject the military draft as the cruelest and worst form of slavery. If our government wants young men to go kill people, they need to make a persuasive enough case to them to get them to agree to voluntary servitude. But then, what if the wolf really is at the door? There's Vietnam, and then there's World War II.
Watching this cartoon closely, though, Bluto didn't actually get drafted. After spending most of the show trying to get injured, he finally got his "exception." But when he sees the enemy pounding Popeye, he volunteers. One interesting bit that I've never seen in any other Popeye cartoon: He ends up feeding spinach to Bluto. Bluto on spinach is Bad News for the emperor.