It's not the first time ol' Bats hit a Robin. We all know the famous Batman slaps Robin meme. Punching Robins is only a small percentage of people Batman hits on the reg. Most of them are criminals and occasionally he might throw a punch or 3 at fellow Justice Leaguers.
See folks, Batman hitting Robin is not out of character for those who think he lost his mind (which he kinda did so far). Other than that I really just wanted to talk about Batman hitting people no matter who it was. Well, thank you for reading this slow news day article. See ya around hot geeks.
Slow News Day:
Batman's Bat-Punch of Fury