Some reactions to some takes :
_About the stand up freedom of speech.. BS. There is a difference. If say a stand up artist jokes about religion or any political subject, and people threaten him then you have a problem indeed. NOW if you personally insult or joke about ONE person, in the the room, and that people doesn't like it and slaps you, well.. that's a risk yeah lol. There is no freedom of speech there, it's a problem between 2 person.. If your joke is personal, you may have a personal response.
_Interestingly, about what is a slap. If the wife did it, nobody would have ever talked about that whole physical violence thing. If someone says something really not elegant to a woman, and she slaps in response, you're not going to hear about shocking violence. People are going to be all "yeah girl well done!"
Now the husband did it and i recall a woman journalist in France saying it was basically a sexist macho thing to protect his wife lol. And also suddenly a slap is like a shot gun or something.
When a slap is (i said it back then already) the most polite form of violence. It's the act of not punching someone, it's symbolical. It's literally removing your glove to slap someone with it like in ancient times! It's the gentlemen violence. I still think Smith acted like a fool but let's not talk about savage violence.
_Finally, about him laughing before. The way i interpret the situation: He witnessed the assault (that was an assault and an humiliation, intentional or not), and had the intuitive reflex to laugh to play the game on tv (he talked about that i think at the end), like he shouldn't react, or revolt. He had to accept the humiliation of his wife cause you don't do waves in that kind of show, you's a good boy and you shut up. Then he immediately felt super bad about it seeing her, and felt so guilty that he had to do something.