One of Kate Chopin’s goals in writing the short story “Desiree's Baby” was to show the damaging effect that racism has on people. Chopin does this through severe irony.
Chopin sets up the character of Armand, husband to Désirée and father of their child, to be a harsh master. Désirée tells her adopted mother, “he hasn't punished one of them—not one of them—since baby is born.” This is meant to show how his love of the baby has changed his harsh demeanor to one of kindness.
All, however, is not meant to stay peaceful as Chopin has Désirée notice that the baby has similar characteristics to a slave boy. When Désirée asks Armand what it means, he claims, “the child is not white; it means that you are not white.” Armand's attitude immediately changes as Chopin writes:
“He thought Almighty God had dealt cruelly and unjustly with him; and felt, somehow, that he was paying Him back in kind when he stabbed thus into his wife's soul. Moreover he no longer loved her, because of the unconscious injury she had brought upon his home and his name.”
Armand passes the rage and betrayal he feels onto Désirée and the child. This leads Désirée to drown herself and the baby rather than to feel the pain of rejection from her one true love.
The death of Désirée and the child would make this a most tragic story but Chopin is not finished. She shows the truth of Armand and Désirée’s situation. It was not Désirée who was not white but Armand. This tragic secret is revealed in his mother’s letter to his father.
“I thank the good God for having so arranged our lives that our dear Armand will never know that his mother, who adores him, belongs to the race that is cursed with the brand of slavery.”
It is Armand’s prejudices that lead to the death of his innocent wife and child.