Why does the author hate Tonto and like the Lone Ranger?

The author simply states that he has always hated Tonto because he looks just like him. When Sherman Alexie was growing up, he used to watch a lot of movies in which Native Americans were regularly portrayed as bad guys, wild savages nobly vanquished by heroic white cowboys and soldiers. He often used to imagine himself smeared in war paint, riding bravely into battle to fight against General Custer. He identified with just about every Native American he saw up there on the screen, however crudely stereotyped he may have been.
However, Tonto was always an exception. Tonto not only looks like Sherman, he shares similar attributes, and Sherman hates him for that. At the same time, he likes the Lone Ranger. He is a much stronger character; he is an idealized Western hero who acts as a great role model for young boys.
The character of Tonto has been condemned by many critics as a kind of Native American Uncle Tom figure, overly deferential and submissive to the white man. By lapping up the negative portrayal of Native Americans in countless TV shows and movies, young Sherman was effectively turning into such a character. In hating Tonto, he was hating himself and what he had become.