Non-violence is not weakness
When we are the object of abuse or injustice, it is absolutely legitimate to use whatever means might be appropriate, including any necessary force; but never with hatred.
Deep within ourselves, it's important to maintain invincible compassion and inexhaustible inner strength.
It's not a matter of either passively submitting to the mercy of anyone who attacks us, or trying to eliminate them by force (there'll always be more to come), but of discovering that our main enemy is the wish to harm others—something we'll need to combat mercilessly.
That's what we have to understand and, as much as we can, get others to see, too.