The main point that Horwitz is trying to make here is that people like the Alabama woman mentioned in the question have a very selective and biased view of the war. The Alabama woman wanted to have the museum at Andersonville reflect her contention that Northern prison camps were equally bad. She ended up creating her own museum that commemorates Confederate POWs. In this part of the book, Horwitz also talks about the general attitude of people in the Andersonville area to the issue of the POW camp. They tend to see the Confederate commandant of the camp, Henry Wirz, as an unfairly maligned hero. This is an example of how, Horwitz says, many Southerners see the war in a very biased way.