You might think that is a good solution but there was a piece on Medium a while back from a woman who was a double black belt in something or other who was raped. I think a better solution is creating a culture where men don't rape so that women needn't learn to protect themselves.

And I do realize that other people other than women get raped as well, but that also is part of a domination scenario so I didn't speak to it here because my resource materials were about men raping women.