In a NYT op-ed, professor of sociology Neil Gross asks “Why Is Hollywood So Liberal?” He surprisingly makes a token gesture to the hugely disproportionate role of Jews in the industry (!):
The looming threat of anti-Semitic fascism further politicized screen actors in an industry that had become an ethnic niche for Jews.
Unfortunately, this is the full extent of his discussion of Jewish influence in Hollywood. (Neal Gabler’s An Empire of Their Own: How the Jews Invented Hollywood is still the go-to book on this subject. To this I would add Edmund Connelly’s articles on the subject in The Occidental Quarterly, and Joel Stein’s explosive 2008 LA Times op-ed “Who Runs Hollywood? C’mon“.)
As far as why so many actors in Tinseltown are liberal, Gross emphasizes what I’ve long believed: Successful acting requires an inordinate psychological ability or predisposition for empathy:
[I]n a recent paper, the psychologist Adam Waytz and his colleagues report a more nuanced finding: The main thing distinguishing liberals and conservatives in this regard isn’t how empathetic they are overall; rather, the key difference is how much empathy they feel for specific groups. Where conservatives empathize foremost with family members and country, liberals extend the bounds of empathy to include friends, the socially disadvantaged and citizens of the world, to whom they’d like government to lend a hand.
Jonathan Haidt has covered similar terrain in his work on the bifurcated routes personal morality can take, leading some to liberalism and others to conservatism.