A 1950s-era Superman poster is going viral on social media. In the poster, Superman addresses a crowd of young people about the importance of respecting multiculturalism in America.  The poster seemed to be aimed at school-aged children and teens as it says "HELP KEEP YOUR SCHOOL ALL AMERICAN."

Imgur - imgur.com

The text of the poster reads:

"...if YOU hear anybody talk against a schoolmate or anyone else because of his religion, race or national origin - don't wait: tell him THAT KIND OF TALK IS UN-AMERICAN."

What's interesting about the poster is the time period in which it was made. The post-war era of the 1950s is often seen as a repressive period that emphasized conformity, but this poster is a reminder that even then Americans were concerned about tolerance and respect for other cultures.

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Throughout Superman's existence, he's often been used as a political symbol. In the 1930s, he was portrayed as a hero of working class Americans. Writing in the Washington Post in 2013, Glen Weldon described how Superman stood up for the little guy in the early comics:

"As the nation emerged from the Great Depression, Superman went after those who would trample on the rights of honest working folks. He triggered a cave-in at a coal mine that trapped its wealthy owner underground, exposing unsafe working conditions. He terrorized a corrupt Washington power broker by tossing him around the Capitol dome like a rag doll. He torched an oil well, bankrupting its crooked stockholders. Artists often depicted him gazing past the horizon, burnished by the golden sunrise of a new day — iconography straight out of a socialist mural."

Later on, he represented American foreign policy abroad, in World War II, Vietnam, and in the Cold War. Here's Superman battling Adolf Hitler and Japanese Emperor Hirohito during World War II:

Crossover Bureau - bureau42.com

It's not exactly P.C. by 2015 standards.

Today, we've seen Superman inserted into race relations. A comic from earlier this year, created by Greg Pak and Aaron Kuder, shows Superman protecting protestors from police:

DC Entertainment - dccomics.com

Related: New Superman Issue Sums Up the Struggles Against Police Brutality

In America, comics have always been a refection of contemporary political and social issues. And this 1950s Superman poster is going viral because we're having the same conversations today — whether it's debating race on college campuses, police treatment of minorities, or Islamopobia after the Paris attacks.