No it's not okay. The warrior role is one of power - it's masculine, and for a woman to usurp that role is against nature.
Moralising aside, it's stupid. Films like this are giving impressionable young women the idea that they can take down a man thrice their size in a physical confrontation when what will happen in the real world is they'll freeze up in fear or be physically overcome, and their assailant isn't going to stand there waiting for her to hit him.