If you had a friend you had known since Pre K and they ended up becoming a delinquent, then a criminal, and your other friend wants to help him relive his life, would you kill him? Because Sakura's a teenage girl who was affected by those feelings, and it's not easy on her. She couldn't bring herself to kill Sasuke, and the pressure of her depending on Naruto and her memories made it worse on her. She isn't useless for that. Why, as a matter of fact that just shows she has personality. I see it pretty natural to not want to kill a friend, but under these circumstances? And she's learned to heal and save peoples lives? Without her Chiyo wouldn't have beaten Sasori.. I seriously can't stand it when people bash on Sakura just because she isn't as OP as the other characters. Sorry, but you're opinionated based on how powerful she is. Try to think about how the character feels before you bring up her not wanting to kill an old friend.