[legion]

Moses had a thread on this very topic a few years ago.

Yes, they can and will fire your son for not joining the union, even though he is working for minimum wage and gets no benefits--thus the union does nothing for him other than suck his wages. Most "blue" states have "union shop" laws that require employers of a unionized workforce to hire only union members. Your son has something like 90 days to join or he is gone.

Me? I wouldn't join the union, tell them to eff off, and keep collecting a paycheck until fired.