J'onn would see his family die by the white Martians, he fled from Mars and landed on Earth when he saw the Darkseid invasion, a green lantern would be killed and its ring would be flown to J'onn. He denied the request because he couldn't even save his family, he watch Clark grew into Superman. He adopted an identity for himself, Calvin Swanwick, he joins the Justice League as Martian Manhunter.
