1.
The Basic question is if you regard violence or even civil War acceptable to change a surpressing Society like hvite people keeping Blacks as slaves...
The French revelution was basically an uproar against a very rich ruling class ny very poor, starting people.
By very poor starving people where the killed royalty and nobelmen / women...
The American revelution ( not the civil War which was fought to end slavery) was against the British rule since the USA then was a British colony.
The Haitian revelution was against the French rule which also allowed slavery, but as far as I know ended in splitting Haiti in 2. One sovereign country and one still French colony.
However, the main theme is if violence and killing other people is acceptable to end colonial ruling and / or slavery or other very unfair situations...
I will answer the question that is sometimes is necessary to be violent and even kill the rulers if they stand for an inhuman treatment of other human beings.
However it may be difficult to judge what is inhuman treatment some time so an unconditional YES is not the right answer either....