Can someone explain to me the difference between...

Right to Work states and At Will Employment states?

And are there states that have neither policy?

A right to work state says that a Union can't make membership and dues payment mandatory. I have no idea about the other.

means they can fire you anytime, for anything or nothing. First hand experience.

At Will Employment states. I was listening to a program on slavery and the Underground Railroad the other day and the thought that occurred to me was, what is the difference between slavery and undocumented or guest workers? The same states that supported slavery in the 1800's are Right to Work southern states and generally vote Republican and use the same argument supporting illegal immigration as they did for slavery in the 1800's. You always hear the BS that Americans won't do that kind of work, isn't that the same justification they used for slavery? So you deliberately leave the boarders open and have no serious penalties for hiring illegal workers so greedy Americans can get cheap workers with no rights. In my opinion there is little difference.