what is atticus attitude about fighting the case?

Atticus feels it his duty to deffend Tom Robinson. Even though the odds of winning are stacked against him, especially in racist Alabama, defending tom is simply the right and etical thing to do. Atticus knows this trial might be a losing proposition but he feels that he must try for the sanctity of all that is right in the world. Atticus adds that if he didn't deffend Tom,  "I couldn't even tell you or Jem not to do something again."

what do u mean by "especially in racist Alabama, defending tom is simply the right and tical thing to do". What does it being right and etical have to do with especially in racist Alabama?

Hi, one of the running themes is of the old racist attitudes of the American South  still being fresh in the minds of the minds of citizens in Maycomb Alabama. The bitterness of losing the Civil War still resonated in the American South. This bitterness combined with generations of racial oppression ingrained in people made Alabama a very inhospitable place for Blacks during that time.