Tom Dennison of Minneapolis, above, an Army veteran of the Vietnam War, closed his eyes during a moment of solemn reverie in Lakewood Cemetery during Monday’s Memorial Day service in Minneapolis.

At right, Drew Cutkomp of Des Moines walked alongside his grandfather, Warren Ditch of Minnetonka, near the Soldiers Memorial monument at the cemetery. Ditch served in the Navy in the Pacific Theater during World War II.

Memorial Day, which began as Decoration Day with the ­placing of flowers and flags on the graves of Civil War soldiers, was expanded after World War I to honor all Americans who died while in military service. Congress didn’t pass a law making Memorial Day a national holiday until 1971.