This is only my opinion, and I acknowledge that I DON'T have all the data to back up my opinion. I base my opinion solely upon my own personal experience with unions and my casual observation over some 20+ years.
Unions cannot protect your job. How many unionized airlines no longer exist because their cost structure was prohibitively high, and the unions representing the labor force refused to help management adjust to changing market conditions by negotiating fair cost reduction measures? It seems like they'd rather strike a company out of business than negotiate reasonable and fair consessions.
Now, I'm quite sure that "mangement" has a lot of house cleaning to do in this department too. They need to stop paying outrageous salaries and bonuses to themselves when the "chips are down". They also need to negotiate in good faith and not build a "cash war chest" with the aim of busting the unions, but rather realize that their "workforce" is their MOST valuable company asset! This "us against them"/"master vs. slave" mentality is arcane, inappropriate, and has no place in dealing with today's highly educated and technically proficient workforce.
Unions spend a lot of valuable "company time" and "company money" protecting the jobs of those who deserve to be fired!!! I have seen this first-hand!!! If the unions would discipline their rank and file to be efficient and productive by putting pressure on their "brothers" who constantly push the "abuse envelope" instead of turning a blind eye to their costly tactics, rather than going to bat for them, at all company cost, when they get caught "red-handed", they could "raise the bar " of performance instead of "dumbing down" everyone else to the lowest common denominator!
Management needs to do their part too! Quit paying "top dollar" for those jerk-offs who know how to "pose", spit out the "boardroom" rhetoric, do the "tribal management soft-shoe" in company meetings, but DON'T respect their empolyees and CAN'T get along with the workforce because they're too busy feeding their egos, maintaining their professional facades, and focusing solely on their own personal agendas! I've seen that first-hand too! Those types can never lead the company to profitable results! Quit handing out "golden parachute clauses" to the self-proclaimed "geniuses" who can't produce the results you expected of them when you hired them! Give them the same "boot-in-the-ass" you'd give anyother employee when they don't perform as expected!!!
A union shop steward once told me this during a contract renewal process when I was part of the "rank and file". He said, "We don't want to break their balls, Don. We just want to sqeeze them til they start sweating!" This "more, more, always more!" mentality of unions has to stop! It ultimately costs their membership jobs rather than producing them! We all know that "management" would be slave-drivers if they could get away with it, but the union mentality of "how can I get more for doing less" is just as bad!
So finally as to the question of "union, yes or no?" I say show me a "good union" that has a proven record of serving their membership, that isn't led by a bunch of uneducated "red neck yahoos" that only know how to agitate rather than co-operate, can give me a replacement job of equal or better salary when the result of their call for a strike results in the company going out of business altogether, a union who'll pay my full salary and benefits while I'm on the strike they called for, a union that won't do the things I mentioned above, and I'll join it and vote for it. I've never heard nor seen one of those kind of unions. So frankly, I'll take my chances depending on myself, my work ethic, my talent, and my own initiative!!!