The old unions such a the IWW and Knights of Labor were real unions in the true sense of the word. Once govt and Corp. America destroyed those unions and created contract management, labor was effectively dead and only the years need to roll by until they came to realize it. 100 years later we have reached that reality.
Next year UPS will for the most part dictate terms and the IBT will snap to attention and say yes sir. I see little else in the way of any other option.