Elia Kazan and pinky?

This movie preceded HUAC hearings by several years. However given Elia Kazan's prominence in the the hearings how can one miss the connection of Pinky to pinko. Does it ask the question if someone dabbled in communism in their youth does that taint them in the way that Pinky was tainted. It becomes reminiscent of the "Crucible."

Perhaps someone knows if the anti-communist hysteria that came to a head with McCarthy was preceded by smoldering in the late 1940s.