At one time in this country, there were few workplace safety laws, few restraints on employers, and incredibly exploitive working conditions that ranged from slavery, to share cropping, to putting children in dangerous working conditions. Unions, to their everlasting credit, helped play an important role in leveling the playing field for workers.
However, as the laws changed, there was less and less need for unions. Because of that, union membership shrank. In response, the unions became more explicitly involved in politics. Over time, they managed to co-opt the Democratic Party, pull their strings, and rewrite our labor laws in their favor.
As Lord Acton noted, "Power tends to corrupt," and that has certainly been true for the unions. Unions have become selfish, extremely greedy, and even thuggish in their never-ending quest to take in as much as they can for themselves, at the expense of everyone else who crosses their path.
That's why today, unions have changed from organizations that "look out for the little guy" into the largest, most rapacious special interest group in the entire country. Where unions go, disaster usually follows. Just to name a few examples:
1) Unions are severely damaging whole industries: How is it that GM and Chrysler got into such lousy shape that they had to be bailed out? There's a simple answer: The unions. The massive pensions the car companies paid outraised their costs so much that they were limited to building more expensive cars to try to get their money back. They couldn't even do a great job of building those cars because utterly ridiculous union rules prevented them from using their labor efficiently. America created the automobile industry, but American unions are strangling it to death. Unions also wrecked the steel and textile industries and have helped drive manufacturing jobs overseas. They're crippling the airline industry and, of course, we can't forget that...
2) Unions are ruining public education: Every few years, it's the same old story. The teachers’ unions claim that public education in this country is dramatically underfunded and if they just had more money, they could turn it around. Taxpayer money then pours into our schools like a waterfall and....there's no improvement. A few years later, when people have forgotten the last spending spree on education, the process is repeated.