Alma 43:45

"Nevertheless, the Nephites were inspired by a better cause, for they were not fighting for monarchy nor power but they were fighting for their homes and their liberties, their wives and their children, and their all, yea, for their rites of worship and their church."

The Lamanites want to destroy the Nephites because they worship differently.  Lamanite leaders want to rule over the Nephites and gain glory, money, and land.  Nephites only want to protect what they love and hold sacred.  Many Nephites died fighting to protect their families and religion. Although there is not actual war today against the Church, Satan has riled up so much hatred against us.  We need to have the courage that the Nephites had and be willing to sacrifice to protect what we love.