Actually, "Arizona" did not refuse to honor MLK. Our governor at the time rescinded the holiday because it had been passed in an illegal way by the previous governor. While technically he was right, he never should have done that.
But, before you try to stamp AZ as a racist state, the people of Arizona voted OVERWHELMINGLY to adopt the MLK holiday. And, we are the only state that allowed its voters to decide on this. I'm sure that if all 50 states would have put it up to a vote back in the 80's, there would be a few that wouldn't have passed it. And, America West observed MLK from day one, even when the state didn't.
Don't fall into the old "Arizona is racist because of MLK" baloney unless you know the facts.