AZ is an "at will" state, and I'm so happy it is.
I tell people all the time that I know I'm not indispensable, I strive to make myself less dispensable by doing a quality job for my employer, and get more jobs based on my skills and knowledge through word of mouth.
I've landed us some pretty big contracts from my skills, and was even requested to do the work personally. Had I been a union guy, I don't think I'd have the incentive to do better.
Thing is, when I first came to the company, I had a supervisor that hated me, and even he didn't know why (he told other employees this info). I didn't get hired full time after the first probationary period because of him. Two months later, I was hired full time, and a few months after that, they canned the previous supervisor. I now have what he had, truck, raise, elevated status in the company.
I had to prove my worth to them, and now, it's all a bad memory, but I still strive to be the best employee in the company. And no, no brown nosing for me, I don't need to with my performance. Even when I've screwed up, I told them up front what I'd done, and even offered to fix it on my own time. Never heard a word about it, just make sure it doesn't happen again. That AZ heat can sometimes fry your brain when making critical measurements
Have a great gun carryin' Kenpo day