Read Lincoln’s statement from "The Gettysburg Address." 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.

Lincoln’s use of brevity

highlights how many brave soldiers died during the war.
allows him to avoid describing what people should do next.
clarifies that people have to continue the work of the soldiers.
encourages people to feel grateful that they are still alive.