"Hitler ruined that mustache for the rest of us."
It's true too. Culturally, western society so strongly associates Hitler's mustache with a genocidal dictator that even seeing it conjures up an emotional connection. I find it fascinating that a man has been so thoroughly associated with his mustache that more than 60 years after his death, people would face social stigma if they wore it. This is a testament to the effectiveness of the the World War 2 propaganda. Hitler's mustache and right-to-left hair part became icons that were easy to caricature:
That meant American propaganda wasn't America versus Germany; it was America versus Hitler. Mentally it's much easier to view a person as evil than an entire nation, so Hitler became the face of evil. Here's one of my favorite propaganda posters:
Yes that's right. When you ride alone, you ride with Hitler! The poster's message was that you waste gasoline when you don't car pool, and this in turn hurts the war effort. Technically stated that wasn't true. Commodities like gasoline, bread, and meat were strictly rationed on a nationwide level, so that the war effort would always have enough of these things. From an economic perspective, if the general public consumed more gasoline, then the price of gasoline that the public had access to would increase, but it would have no effect on the quantity of gasoline the soldiers could use. The rationing merely makes publicly accessible gasoline more price sensitive. Put another way, you don't even have access to gasoline until the army says it has enough, so buying more gasoline only affects what you and your neighbors will pay.
Of course, the poster's message is still in the viewer's best interest even if the logic is incorrect. Somehow "When you ride alone, you pay more for gasoline" just isn't as compelling as "When you ride alone, you ride with Hitler." Propaganda works because most people don't think rationally. The emotional connection of "Hitler is a bad guy so I won't help him" is easy to reinforce through caricatures. But the logic of "Because gas prices are high, I should save myself money by using less of it" is too subtle to convey through a simple poster with a one line slogan.
The propaganda is a lie that encourages people to do things in their own self interests. Do the ends justify the means in this situation? I don't think so, but then again I'm a purist. I can certainly understand why people would disagree with me.