the ability to unionize is determined by the laws of the State -
rum, very rum indeed.
Over here all citizens have the right to form unions guaranteed by the Constitution.
I'm a librarian and a union member, and it paid out. When government decided to raise weekly working hours to 42, we union members still kept the old contract and are still working 38,5 hours a week. And that is enough. When the pay must be raised we are ready to strike.