I like it so far.

But, if there is no military presence, how did the fleet enforce the orders of the Fleet Admiral? Would it even have been necessary to kill him in order to prevent the ships' retreat back to Earth? I feel like, if there was no military force enforcing the retreat, the killing wouldn't have been necessary, because the Fleet Admiral wouldn't have been able to force anyone to go with him anyway. Those who wanted to stay could have done so without resistance from the Fleet Admiral, since he wouldn't have had the means to enforce the retreat.

Maybe I'm just missing something, though.