Probably the best is the Weber Honor Harrington series, which is kind of a female Horatio Hornblower in space.
Of all the dispositions and habits which lead to political prosperity, religion and morality are indispensable supports. In vain would that man claim the tribute of patriotism who should labor to subvert these great pillars of human happiness, these firmest props of the duties of men and citizens. - George Washington, Farewell Address