Epsilon Reticuli was a setback to The War effort.  Third Fleet was the most powerful force assembled by the Terran branch of humanity in living memory.  It was supposed to break the back of the Shang invaders.  It failed.  Serenity was a Core World, defended by the best orbital forts and defense fleets we had.  They failed too.  And then there was Los Angeles.  That ship does not like to fail.

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