It isnt so much direct propaganda as conditioned propaganda. Stan Lee was a playwright for the us army a title I believe less than 10 people held at the time. He spent his late teens and early 20s being the hand on the page for the voice of the US government. Being immersed in those ideals it is no wonder he regurgitated us red scare propaganda and he expressed regret for it.

This didnt stop though and with iron man stan lee said:

“I think I gave myself a dare. It was the height of the Cold War. The readers, the young readers, if there was one thing they hated, it was war, it was the military. So I got a hero who represented that to the hundredth degree. He was a weapons manufacturer, he was providing weapons for the Army, he was rich, he was an industrialist. I thought it would be fun to take the kind of character that nobody would like, none of our readers would like, and shove him down their throats and make them like him … And he became very popular.”

Prpaganda is defined as

“deliberate, systematic attempt to shape perceptions, manipulate cognitions, and direct behavior to achieve a response that furthers the desired intent of the propagandist”.

Iron man certainly seems to fit. Remember Stan Lee was in the military when it was antifascist. As a result he was pro military and he used his position to sway people toward his own views which… were developed when writing for the army. …

It doesn’t have to be a secret conspiracy to act as propaganda. Social conditioning reinforces it. Americas civil religion permeates every aspect of life from the pledge of allegiance in kidnergarten to the anthem at ball games. If you do not recognize it and challenge it you will repeat it.

I personally think in the case of Batman it was less nefarious. A plot device gone awry. After all, how could a normal man compete with Superman? In our society he would have to be rich to fund his inventions and afford superhuman tools.