There is authority and there is coercive authority.

The latter is an act of aggression and when I'm aggressed upon I have every right to defend myself, by any means necessary.

Which doesn't mean it's the most practical thing to do. But even if they throw me in a cage for defending myself, I still had that right, it just wasn't respected, because that's what coercive authority does: it disrespects the rights of the individual.