When describing her thoughts aboout Underwood's editorial, how does Scout show that she has not lost all of her childhood innocence, but is beginning to understand the implications of racism?

From the text:

"How could this be so, I wondered, as I read Mr. Underwood’s editorial. Senseless killing—Tom had been given due process of law to the day of his death; he had been tried openly and convicted by twelve good men and true; my father had fought for him all the way. Then Mr. Underwood’s meaning became clear: Atticus had used every tool available to free men to save Tom Robinson, but in the secret courts of men’s hearts Atticus had no case. Tom was a dead man the minute Mayella Ewell opened her mouth and screamed."