Just for the sake of smacking the hornet's nest with a stick a little bit: Can anybody name an industry in this country that unionization has not either destroyed or brought to the brink of destruction?
Bueller?
... anyone...?
Not the Steel Industry. Nor Textiles, Rubber, or Railroads either. Surely there must be one, isn't there?
OK, carry on...
While there may be a order to the life and death of a profession (like a thunderstorm stages; developing-mature-dissipation), new-mature-dying, it's hard to argue a profession would end due to a union's existence. A group of professionals who elect a union may exacerbate the union's pull or contract and make a violent/noisy end of a profession, but unions don't kill anything in this country.
As a profession matures, and it goes from highly technical to layman, you'll will see workers push for a union. Why does this happen? Many reasons. Professionals in the career watch more people come, the job gets simpler with tooling and they may want to try to retain QOL and pay. You may have valid safety and career protection concerns that arise over time that a company won't deal with. Certainly there is a myriad of other concerns employees want to address. A union can sometime delay wage and QOL erosion, however these guestures don't do very much but delay the inevitable.
Is it possible for this union to, over time, kill a goose? Certainly, however only for their company (company is the goose). If other companies come along and thrive with no union employees that could be proof the union killed the company. Although other companies seem to exist just fine with a union shop. That's because unions vary so much from employee group to employee group, never mind a different union representing the same profession (IBT vs ALPA as an example).
The death of a professions can be a murky subject, as an example you can look at employees in a union avionics shop. If a Honeywell needs testing on a box (avionics set), they have to use their union shop. From time to time environmental testing Honeywell needs isn't something that can be done in house, and the box is sent out. Any work that can be done by a shop employee (running a rented diesel 400hz generator for instance) must be done by them. On top of that, when someone from the environmental testing shop is working on Honeywell's box a equal number of people must be paid their travel wages while sitting back home in Rockford (or at work, so an effective double pay split among the testing staff). So while I am testing a box, two guys from Rockford would work with me running silly crap I could do myself after being shown, but Honeywell has to pay them to work those status computers and diesel generators. I know some of your heads are exploding so I'll standby... ... ...
Now someday the manufacture of these boxes will be "revolutionized" and the employee driven model may not work anymore. Instead of row after row of Nasa tested soldering minons, dozens and dozens of engineers, tech and testing spooks (E3 guys are often called spooks), and the managers making the process move efficiently, you may end up with 20 or so robots cranking out boards and boxes like taffy. When that happens a bunch of union employees will lose their livelyhood, and I'm sure a few of you will cheer. Right now though, the market does support their wages (through sales of widgets) and a mature well paid workforce presses on.
Does the union kill the profession, will it? No. A union can sometimes kill a company. Someday a group of professionals may be replaced by tooling or computers. The fight at the end may look like union drama, as the last gasp of a profession is whittled away like the copyists of ages ago (before typewriters).
But how about professional horse shoeing, electricians, or plumbing? Many of those jobs are still union and sometimes entire geographic areas are closed to shops. Horse shoeing still costs about $70 a hour, but the car is still out there. Certainly there is no need for a giant army of horse shoers anymore, the numbers of professionals are thinning if not stagnate. Nothing is dead.
Be careful how you think about this topic. Professions are born, mature, change, and die. Sometimes they may be born, mature, change, mature, change, mature, and it's a 100 years later and they are still around, to die someday in the future. Unions provide a voice to the professional, but never can they tell the market to support their wages indefinitely. It is possible to delay the inevitable for years at a time, but soon enough whatever part of the market that holds up those professional wages (artificial now by some delay tactic) will collapse. Unions may prolong death of a skilled job, they may do wonderful things to increase the QOL and pay and safety of a profession, but ultimately the union does not kill a profession any more than it creates it.
Yes I know this is WAY too long of a response. I wouldn't even read the whole thing.