Does political violence ever
work?
Short answer: yes.
Longer answer: Yes, but there are a whole buncha problems, not the least of which is violence attracts monomaniacal assholes like Lenin who double and triple down and keep increasing scope until they create a machine as vicious as the one they are replacing.
But, under well-scoped circumstances, with
SMART goals, and full accountability, yes, sometimes the only way through is to blow it up.
The rulers use violence
all the time but either drape it with state power or just go ahead, do it, and then somehow magically never pay. The wealthy either own the actual police or buy their own. Those who try to protect rights will at times have to use the same measures. If for no other reason than to persuade the rulers to deal fairly.
Martin needed Malcolm to make his "non violent" movement work. Likewise, there were really violent insurgencies who operated during Gandhi's protests and legitimized them as a preferable group to deal with, rather than just blowing them off (or murdering them).
I'd say the way you keep it from going off the rails is once your goals are achieved you surrender to the authorities and trial and accept accountability. You say "here's why I did this," and use your prosecution to spread the reasons why you were driven to violence, having been denied other "legitimate" means. "When in the course of human events..." and like that. And, of course, if they decide to shoot you, welp, you take it.
Lenin aint doin' that.