If a women threatens anyone in any way I would expect the person to do what ever necessary to eliminate the threat be it a man or women. Acting in self defence allows you to hit anyone.
Although if this is one of those anger reasons where the male says "I only hit her because I was angry" then it is not acceptable. If you are angry take it out on birds with a shotgun, animals who are not human or a wall with your fists, hitting another human being in a lower position is not acceptable in any way.
Now Im not saying that you should hit women for the sake of hitting them. I'm saying that if there really is equality in the world there shouldn't really be a reason not to hit women. If women are allowed to hit men, how come men can't hit women? This is what true equality between Men and Women is.
We all know that men are naturally physically stronger and bigger than women. For a man to hit a woman shows cowardice and a short temper, because a woman cannot do the damage with her fists that a man can. You cannot argue this in terms of equality: it is simply a fact that men are typically bigger and stronger than women and therefore should not be allowed to hit women; they could do irreversible damage to her should they crush a rib and cause it to puncture her lungs, or hit her too hard in the head and cause brain damage
You ask generally.I see that as most of the time,is it acceptable.No.Now if a woman is trying to harm you,it is probably ok to strike in self defense.Maybe if its minor,like if you take karate or something and a sparring buddy is a woman.Of course,i dont know much about martial arts.But i digress.I believe Men should not strike women and ALSO women shouldnt strike men.Violence is usually unnesescary.Woman to woman,man to man,man to woman,woman to man,People generallly shouldnt harm other people