Don't you need a job before joining a union?
That line in the story caught my attention also....I had similarly thought that you do indeed need to get hired first, then you join a Union, but I'm no expert on Unions and different Unions may have different ways of operating.
If any Union Experts happen to know, please feel free to explain :-)
You can apply for an apprentiship. They usually accept them yearly (at least in the western PA area). Then you have to wait for them to send you a letter to report for testing. Then you take a standardized test. Then the interview with the apprentiship commitee. Then if accepted, you report for training. At the end of the preliminary training, you join the union. And then and only then can you start working - assuming you have a letter of hire. It's not a bad program - for example the carpenters union keeps training you until you become a journeyman. If I was about 10 years younger, I would have joined.