He would be justified because of how we disobey and sin.
God only creates things He loves. He wouldn't create something He hated. It is not that He has to save us, it is that He wants to save us. He has offered it to all. Hence the scripture that God wills/desires that all be saved. It is not true love if you make them love you by force or programming. True love comes to you when the other has the free choice to love you. This means that people have the choice to not love God, and will receive the consequences of their choice.
Yes, to us it is a marvel He would save any of us. But as it is, love makes you do crazy things. God is love so God must be crazy. Thank God He is crazy for us.