In some extremer cases, the violence could be efficient if it's used only by the states and ifsome persons use it the policy can punish them.The violence is synonym of exploitation of citizens by the states to aim to have some legitimacy. With noviolence, the states lose his legitimacy. So it's a good system of coercion.
But, sometimes, the violence no use any things and just deteriorate. Infact, forinstance in Soudan there was a woman who wore a trouser which is no tolerate in it's country. She was beating up. After that, a lot of womans led a life of combat forsome equality and some rights. They organized many manifestations. I think if Soudan no use the violence, the citizens doesn't disobey.
The violence is a« big word », there was a lot of mens who combat for no-violence like Gandhi in India. The violence can be efficient but only in extremer cases for instance thestates have an army, it is a violence but use in some cases. The no-violence is better because we need a world of peace and liberty, no with wars and killers.