In To Kill a Mockingbird, why does Atticus call Mrs. Dubose a model of real courage as opposed to “a man with a gun in his hand”?
Mrs. Dubose is a very difficult woman. She seems to be unkind and generally grumpy. The children, Jem, Scout, and Dill, are afraid of her. Not only is she misanthropic, but she is very unappealing physically. When Jem "decapitates" her flowers, Atticus punishes him by making him read aloud to Mrs. Dubose. She doesn't seem interested in the stories, but he reads to her a bit more each day. The children realize only later that Jem's reading was allowing her to pass the time, a bit more each day, while she kicked her morphine habit. In the end, she dies free of the addiction and not beholden to anyone or anything. This, Atticus says, is a sign of real courage.
It turned out that Mrs. Dubose was not the person she seemed to be. This is also true of Boo Radley and other characters in the novel and speaks to the idea that you never really know someone until you've walked in their shoes- an important theme in the novel and what Atticus says to Scout early on about the Cunninghams.
Atticus knows that holding a gun does not make you brave. He never tells his children what a sharp shooter he is because he does not see this as something worth bragging about even though his children are impressed and the neighbors seem impressed by this skill as well. But, Atticus realizes that real courage is being able to have inner strength and not just outer strength. Anyone can hold a gun and appear brave. However, not everyone can have the strength to overcome morphine addication. This was an inner battle that she was able to win where most people may not have the strength or courage to enter this fight.
Mrs. Dubose has the courage to end her addiction to morphine before her death, a feat she does quietly while confined to her bed, listening to Scout reading aloud to her for longer and longer sessions. A "man with a gun in his hand" may sport a weapon, but real courage is an inner quality, rather than an external possession.