@Trekker Damian Wayne was genetically and mentally conditioned by his mother to be the ultimate weapon. Since her morales are already compromised as it is she didn't care that her son was a child. As for his age he was ten when introduced in "Batman and Son" not sure his age now. I don't think he has celebrated a birthday yet in the comics.
Read Justice League #2 and admit that it was an improvement over the first issue. I would agree with C. Miller's review though. These seem to be caricatures not characters in the sense that these heroes are stripped down right to their very basic nature of who we all know they are supposed to be and not given much depth. It would also appear that Superman is incredibly powerful in this 52 'Verse. Anyway I liked the issue and the art is good. I guess I will be giving this a chance until the arc is complete.