My brief time on a factory floor in a union shop convinced me to go back to college... and I hated the whole college experience. Up until then, I had never heard anyone seriously threaten to slash someone else's tires or assault their wife.
I was pleasantly surprised that the goons never came back at me after the most recent time I was threatened. I told them that I didn’t want a business discussion to end with someone in a body bag. They never threatened me again and didn’t go after anyone in my family either. I don’t want to kill anyone, but there is no way in the world I’m going to let union goons bully me (plus I do have the training and resources to deal with thugs if necessary - not 100% but odds good enough to bet my life if it’s a choice between that and letting domestic terrorists intimidate me).