From the Fourth of July to Gettysburg Re "Why the Civil War Still Matters" (Op-Ed, July 3): Robert Hicks is certainly right that the war "sealed us as a nation." Not for nothing did Abraham Lincoln avoid the word "Union" in his Gettysburg Address while using "nation" five times. The Civil War, though, matters for another profound reason as well, inseparable from, yet too easily obscured by, emphasis on the first. As Lincoln himself in effect announced in his Emancipation Proclamation and magnificent address, the war amounted to what historians have called a Second American Revolution, one that sealed not just American nationhood but also the kind of country the United States would be. By destroying the institution of chattel slavery that the founders had preserved and strengthened by writing it into the Constitution, the Civil War (and the 13th Amendment) determined that the United States would endure as a free-labor Republic rather than a slaveholding one, and that the country's "new birth of freedom" would encompass, however imperfectly still, black and white Americans alike. The writer is a professor of history at Gustavus Adolphus College. Robert Hicks, in his essay about the sesquicentennial of the Battle of Gettysburg, appears to fear that for most Americans the Civil War is nearly forgotten. Last week, the Supreme Court invalidated a portion of the Voting Rights Act, and Texas immediately moved to tighten voter ID laws and reintroduce a Congressional redistricting plan that was blocked by the Justice Department last year. The Civil War continues to smolder, whether or not we recognize it for what it is. Re "Why They Fought" (column, July 2): David Brooks is right about Civil War soldiers" strong political and ideological beliefs. But his characterization of those beliefs - the sense of duty, the feelings of indebtedness to the past - feels empty and abstract, pretentious, as Hemingway would have put it, without the context. Although Mr. Brooks seems to use quotations mostly from Union soldiers, there were other soldiers who fought at Gettysburg who also used words like "honor" and "duty," but in a very different context. How can we evaluate those soldiers" strong "moral" and "patriotic" feelings, except as expressions of a commitment to the principles of a slaveholding republic? The writer is a history professor at Boston University.