So when is a domestic terrorist (Joe Stack) a hero? Apparently, when his daughter says so (as well as people who "want to follow the Constitution"). However, I think that the son of Vernon Hunter, the person Stack murdered in his attempt at martyrdom, asked ABC News the right question: "How can you call someone a hero who after he burns down his house, he gets into his plane and flies it into a building to kill people?"
Here is an article about Vernon Hunter.
UPDATE: Clearly someone had a talk with the Stack's daughter about heroism. She retracted her comment.