> Consider the possibility that the strong streak of instinctive union bashing that you see in typical professional class culture in the U.S. is very much the creation of decades of aggressive PR effort by those who consider unions threatening.

This is a perfect example of the genetic fallacy. How or why a person came to hold a view tells us nothing about the truth of the view. Even if it did, possibility shouldn't be taken as (or a as defeater for) plausibility. It's possible that unknown to you, your parents are aliens and you were hatched on another planet. It's plausible that you're a human and so are your parents. Similarly, even if it's possible we're all duped by aggressive PR, until I see a very compelling plausibility argument my current experience of observing unreasonable union interference grounds my belief that unions often engage in crude, counterproductive behavior.