AITAH?

So I'm pretty mad right now and need some advice.

My husband saw our 14 month old start spitting (for the first time, so yay us!! We can do a lot with that once we learn it!!) on some toy blocks and raised his hand as if to back hand him and stopped himself. Then raised his hand in a smacking way and stopped himself. I told him not to hit him (my husband was raised in a super abusive and super over strick, expect them to be perfect household and knows his parenting tools aren't always the best), so he tapped him on the hand and said not to spit. I reiterated not to hit our son and why spitting was an important skill for our child to learn and said again do not hit him. My husband got very broody and quite, so I knew I'd upset him. I apologized a few minutes later for overreacting about it, but I didn't apologize for the hitting comments. He angrily said it was fine, but he was pissed. I asked him why and he said let me ask you this. Why shouldn't I be? I told him I had apologized for taking it too far, but he said that he didn't hit him and had only tapped his hand. He said everyone has always treated like he can't control himself his whole life. I told him it wasn't the tap on the hand I was talking about, but the other two hand motions. He dropped it. This isn't the first time this has happened. Another time our child was going to bite and he started to flick him on the back of the head and then stopped when I told him not to do that (baby was about a year old). He said it was a reaction and that he would never have been allowed to get away with it. I am a SAHM right now and handle most of the care and raising of our child. I am okay to stand my ground and this is some the first few times I've really run across rough parenting issues with my husband. He usually lets me have my way and doesn't interfere, so I'm always surprised when he does odd things like these. He's left the room and left me with or son while he's listening to music and cleaning in a different room.

AITAH for sticking up for our son?

Update: I do tell him how to handle things differently and what not to do from a childcare/childrearing standpoint. I explain why and how as calmly as possible. No, I'm not always calm and I do go through the roof at him. He gets very defensive and angry when I do. It's understandable from both sides, but he must grow. I unfortunately don't have family to talk with about this because we were disowned by both sides. My husband thinks he's in peramimeter with some things and we've had a lot of arguing about it. I've just reached a point and place that I needed another viewpoint.

Yes, I've considered whether or not he could do it behind my back. He also knows that won't fly. None of this will. I'm just surprised when he starts to do stuff like this. He's usually so calm and kind with children of all ages. Yes, I've tried discussing therapy with him and it's currently a no go. He does watch lots of self help videos and implements them in his day to day life.

Spitting is a great milestone in my book because once they can spit reliably I can teach them to spit out food when that's an issue or spit out toothpaste, ect. I do not wish our child to spit everywhere, but I do want him to learn to spit so we can teach and learn other things along with that.

Thank you to who have responded and so quickly. I just needed to know I wasn't taking things to far. You have given me some new confidence that I will use to back myself up with as I know this will be a topic of discussion later on.