Fucking no strike clause, what the FUCK
Liberals are fucking moronic scum, we have no freedom, we have no rights, we are granted no provisions for our betterment or even protection or basic decision making
I will destroy this evil land, I will spill the blood of oppressors and free my fellow workers from their chains
I AM RISEN 
It goes back to the AFl. Gompers led a much more exclusionary union movement, and as time went on became more racist and anti-communist. However the reason a trade union federation was needed and is still a great development for that moment is because the Knights of Labor fell apart and fell apart hard. So a more organized "profession" union of trade workers with the specific purpose of collective bargaining directly with management proved effective in a time of serious reversals of labor power.
The problem is these things are not a substitute for socialism, and in fact create a stronger labor aristocracy. I can't blame the craft unions for taking their shot and gaining those wins for themselves. It is a response that sadly makes sense even if you isolate yourselves. And as organized labor is crushed again, it is obvious that the same process is happening.