[Galadriel]

I think I've posted here before (too lazy to check) but I don't think so. Why?

1. Gandalf, Elrond and Glorfindel seem to know him. And Gandalf appears to trust him, though find him irresponsible.
2. If he really was the Witch-King, he would have just ripped Frodo and the others apart at the Willow and not saved their skins.
3. He certainly would not have handed Frodo back the Ring when he took it for a moment.
4. The Adventures of Tom Bombadil would turn into something else.