The English language Wikipedia article on McCarthyism includes an image of an "anti-communist" pamphlet, apparently from the 1950s:
I was intrigued by point 4:
RIGHT NOW films are being made to craftily glorify MARXISM, UNESCO and ONE-WORLDISM.
Why did they care so much about UNESCO? The English language Wikipedia article lists some controversies that might explain why some conservatives are wary of UNESCO, such as the "New World Information and Communication Order" or issues related to Israel/Palestine. However, all those controversies appear to refer to events in the 1970 or more recently, such as when the USA left in 1984 and again 2017. And even then critics would probably hardly consider UNESCO state enemy #1 or focus on it as strongly as this pamphlet appears to do.