I think what we are seeing is a political bandwagon effect you see from time to time, where people join a movement or agree with an idea for the sake of the bandwagon, often without understanding the belief they are joining.

So, taking the phrase "We should teach men not to rape", that is theoretically supposed to be referring to blindspots a culture might have about what rape is. Obviously there isn't a problem with people violently raping people or cosbying people just because they don't know any better. But fucking chicks passed out at parties? Or women who say no, and keep saying no, but don't raise their voice or defend themselves? Well, it's easier to see how a guy, particularly a young guy, might be confused in that department. And seeing as how the person you were arguing with thought the phrase "We should teach men not to rape." meant that guys might know what rape is but do it anyway for some reason... well, I suppose that shows some women are confused in this department as well.

I do absolutely agree with you about the way we use victim blaming in our society though. There is a difference between dismissing a victim for not defending themselves, which is what that term should be used to describe, and giving the victim the tools to protect themselves from the crime, which is something we should promote instead of denigrate. I mean, shit, I agree with a lot of what the mainstream Black Lives Matter movement is about, but you aren't going to catch me strolling around East Saint Louis at night alone. Just because you think there is a problem doesn't mean you should act like the problem doesn't exist.