It is not passivity or weakness. Done right, nonviolence is a disciplined, demanding strategy for confronting injustice, and it has toppled empires and changed laws where guns could not.
Nonviolence is the practice of pursuing social or political change without using physical force against opponents. It is active, not passive: it confronts injustice directly, but refuses to answer violence with violence.
It is a method as much as a morality. Mohandas Gandhi developed it into a systematic strategy, satyagraha, to challenge British rule in India, proving that mass disciplined refusal could defeat a far stronger power without firing a shot.
Martin Luther King Jr. brought it to the American civil rights movement and made it a science of struggle. Activists trained rigorously, learning to absorb taunts, blows, and arrests without retaliating, so that the violence of their oppressors would be exposed for all to see.
Its power is partly strategic. When peaceful demonstrators are met with brutality, public sympathy shifts decisively, as it did after Selma. Nonviolence wins by forcing a choice: the oppressor must either stop, or reveal an injustice too ugly for the public to tolerate.