What vision of the nation does Lincoln describe at the end of his speech: "It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. . . .that we here highly resolve that these dead shall not have died in vain that this nation, under God, shall have a new birth of freedom, and that government of the people, by the people, for the people, shall not perish from the earth."