Even if he would not have done that without the drinking involved it is still it very abusive behavior for a father to
do to his children.
If he does not apologizes, works to make his children feel safe and to avoid this happening in the future and just blames it on the drink... I would call that domestic abuse.
The thing is, his ego is so big, whenever I try to make him understand that he just hit his own daughter, he goes on to tell US that we are a disgrace, we're disrespectful and whatnot. Actually, this is all I can do rant on the internet, because my whole family is normalizing these, whenever I try to talk it out with them they give me lukewarm answers, they don't try to reassure me or even get me away from him, or at least let him know, since they hate him too.
Well it doesn't matter what he says but don't let your family make you think this behavior is normal. It is abuse, you may not ever see them recognize what they are doing is wrong but it should not change your mind.
I hope you can find the strength to get out of this having more integrity that these people

If my father is drunk, and came up to my little sister and slapped her left and right, is it justified? Or was that a depiction of domestic abuse?