What do the children think Atticus should do to protect himself?

In chapter 23, Bob Ewell spits in Atticus's face outside the post office and attempts to fight him. Instead of challenging Bob Ewell, Atticus calmly wipes his glasses and walks away without arguing. When Jem and Scout hear about their father's encounter with Bob Ewell, they begin to fear for Atticus's life. They are well aware of Bob Ewell's terrible reputation and do not put anything past him. Jem and Scout believe that Atticus should carry a gun with him to protect himself against Bob Ewell and any other disgruntled citizen harboring a grudge. They know that Atticus is the deadliest shot in Maycomb but also realize that he would never carry a gun. Jem even tells Scout, "You know he didn’t even have one down at the jail that night. He told me havin' a gun around’s an invitation to somebody to shoot you" (Lee, 221). The children even petition Atticus to carry a firearm, but he refuses to and tells them that their idea is nonsense.