Krishna teaches the art of reconciliation through the analogy of his friendship with Madri. Everyone in Kaurav’s camp also regarded Krishna as the Supreme God.
Apart from Yashoda and Arjun, Krishna shows The Vast Form to Duryodhan also. For Krishna everyone was same. Krishna does not facilitate killing of any individual in particular but annihilated the entire Kuru cult including Pandavs and Kauravs side.
Krishna does not protect the perishable and asks Arjun to aim for larger goal of life