I grew up in Pittsburgh, was there in the 70s and 80s and graduated from Pitt. I was there during the big collapse (implosion) of the steel industry. My take on it: unions killed the US Steel industry plain and simple.
After high school I could've gone to work in the mills. Instead I went to college. 4 years later when I graduated, I started out making less money than I would've been making if I had 4 years experience at union pay scales. I'm not sure that I have ever really caught up - if you factor in benefits, automatic pay increases, vacation, etc.
The unions had a strangle hold on the companies. Tremendous starting hourly rates, vacations, benefits packages, raises. The unions were really trying to in-effect run the companies. You couldn't base pay on performance (or lack thereof), you couldn't hire (non-union) or fire/lay-off. Couldn't change someone's job without a renegotiation, etc. etc.
So yeah, they had a strangle hold on the companies, and were running them, at least the labor side of them. Unfortunately the union "leadership" was short-sighted and power hungry. They ended up strangling the companies and running them right into the ground. I can remember the glow of the big furnaces at night from J&L, US Steel, and others. Now that area is waterfront retail and upscale apartments if I remember correctly.
Don't get me wrong - I'm all for protecting the worker, fair pay for fair work, not letting the company take advantage of anyone etc. But what the workers really had was the union taking advantage of them, using them as leverage to get money/power from the companies. In the end, it would've been far better to be employed at $10/hr rather than unemployed at $20/hr.
Sounds like you must have a good grip on the auto industry collapse in MI as well.