The Conquest Of Makkah
Assalam-o-Alaikam. I am not a scholar, but here is my opinion. He was thrown out of his home from Mukkah and he just wanted to return to his ancestoral home and Kuffars won’t allow it without a war. Also Kuffars won’t even let him live in peace in Madina either. When fighting is imposed on you, a Muslim must fight. Also there was no killing outside of battlefield when Mukkah was conquered. No revenge was taken from Kuffars outside of battlefield.