If someone submits a comment and impersonates you, can they be sued for one of slander/libel/defamation? Can they also be sued for identify theft? If someone

If someone submits a comment and impersonates you, can they be sued for one of slander/libel/defamation? Can they also be sued for identify theft? If someone can be sued for making a false statement about you, why not when they willfully and knowingly steal your identify to make others believe you did something that you didn’t?