I think that because Baba hurt Amir so badly by never revealing this fact, he caused Amir to become overprotective of Sohrab's emotions. When General Taheri calls Sohrab a "Hazara boy," Amir almost violently retorts that Taheri "will never call… [Sohrab] by that name again in… [Amir's] presence." I think this shows that Amir's relationship with Sohrab in America is desolate, bereft, and ready to fall apart at any given moment. I hope Sohrab will eventually open up to Amir, and I wonder if Amir will always accept Sohrab for who he is in the