The key to understanding The Searchers is understanding that Ethan Edwards' mother had been killed by the Comanche when he was young. We see the inscription on her tombstone when Scar finds debbie in the raid. It turned him into a bitter racist who lived to hate. The movie starts when he returns to his brother's ranch a few years after the Civil War. His brother's place is then attacked and the family is massacred. Ethan begins a five year long search for his kidnapped niece.
As his niece Lucy comes of age, Ethan would rather see his niece die than live with the Comanche. People who have said that John Wayne can not act have never seen The Searchers because he is just great in this.
The leader of the Comanche is a warrior names Scar, who physically represents the scar on Ethan's psyche. His family has also been destroyed by his enemies, the white invaders. Both men have a reason to hate. Scar has lost two sons to the white invaders. Ethan has lost his mother, Martha and his niece Lucy to the Comanche.
Scar is a mirror representation of Ethan. They are both racists because of experiences they have suffered. But, Scar can be looked upon as patriot fighting against foreign invaders. Martin is the true hero of the movie. He is the one who points the way for Ethan.
The Searchers is a tremendous movie. It is not a great exploration of the Indian way of life. It is a great exploration of racism and is an important movie about America facing up to its treatment of Native Americans and other minorities. It is very important that the movie welcomed back in to the American household Martin, the "half-breed" and Debbie, the "leavin's of Comanche bucks". This was an important statement for John Ford to make in 1956.
Ethan developed as a person during the movie. He accepts Martin as a person, even though he is part Indian. He brings Debbie home, even though it had looked like he would kill her. But Ethan still can't enter the household at the end. He can't bring himself to enter the home where the races are mixing. It wasn't the typical Hollywood ending, which is one reason why the movie is so good. Ethan has made progress but there is still a long way to go.
In his book, Gunfighter Nation (1992), Richard Slotkin says of The Searchers: "The moral confusion of the ending is responsible for two recurrent misreadings of the film. A 'left' misreading sees it as an exemplar of the very racism it decries. A 'right' misreading sees Ethan Edwards as an entirely heroic figure whose harsh manner and personal isolation are the consequences of his devotion to his mission and his unique understanding of the red menace. Both misreadings were and are responsive to the ideological crisis over civil rights and foreign policy that began in th mid-fifties and culminated in the era of the Vietnam War. Ford metaphorically explores the logic of the 'savage war'/Cold war analogy, which he himself so eloquently stated in Rio Grande, and finds that it produces an overwhelming and finally malign, pressure to choose 'destruction' over 'rescue'."