Yeah, it’s a red card. You cant go around jabbing at people.
that's not an easy sequence to officiate. Kane acted like an a$$ before the incident that resulted in a red card, between pushing down the defender, then kicking his leg while trying to get the ball, then grabbing Doucoure's jersey, etc. And Doucoure's action could be looked at as just attempting to break Kane's hold of him. Kane then really sold the idea that he was hit in the face.
Refs don't like players taking a swing at an opponent, but Doucoure's action was more of a swipe than a swing, IMHO.
If I were reffing the game, I would have given a yellow to Kane and a yellow to Doucoure. I felt that Kane did more than enough outside of the acceptable, and so he would have gotten a yellow for unsporting behavior. And I would have given Doucoure a yellow for the same infraction, and also had a chat with him to inform him that he was on the edge of getting a red, and better improve his behavior.
I haven't looked at the official stats, but I'm guessing that the ref gave Doucoure a red for violent conduct, and I just don't think his actions rise to the level of violent conduct.