Their leadship has alway been stupid.
Back in 1982 I received my monthly magazine from the United Association of Plumbers and Steamfitters which had a piece in it from the UA President telling members to support congressional election of the candidate that was most likely to support construction related issues regardless of party affiliation. I showed it to my dad who was totally anti-union, and he about fell out of his chair.
As an now ex-union member I cannot understand the fascination of unions to support leftist candidates. They give their money to them then get kicked in the ass because their candidate supports all of the other job killing causes.