Yes, yes, and yes.Morality questions:
1) Is a slave morally justified in killing his owner?
2) Is a slave morally justified in killing an employee of the government whose job it is to enforce his slavery, e.g. police, army, etc?
3) Is a slave morally justified in killing someone who actively works to keep him in slavery, e.g. a politician?
Reword the question in a more historical context and see what the answer is.
If your country is occupied by another country (ie occupied France during WW2), is it ok to shoot foreign soldiers? Of course it is. Is it ok to shoot the commanders who tell those soldiers what to do? Absolutely. Is it ok to shoot the politician who told them to invade your country? Well the US spent several years trying to kill several of those people (Hitler/Mussolini/Hirohito) so that too would be a yes.
