War is violence committed by one state against another. Revolution or terrorism can be violence committed by a group against a state or innocent civilians. As there can be just wars, so can there be 'just terrorism'. Terrorists (or violent revolutionaries) only become freedom fighters and statesmen if they are successful in their terrorism eg Nelson Mandela, Gerry Adams, Martin McGuinness. Good government entails the prevention of grievances that cause acts of terrorism to be committed, and bad governments deserve to be overthrown.
Do the ends justify the means? We can only wait and see.