Who Should We Honor on Memorial Day?

In 1866, four women placing spring flowers on the graves of Confederate soldiers at Friendship Cemetery in Columbus, Miss., noticed that the nearby graves of Union soldiers were barren. They took it upon themselves to decorate those, too.

Lately I have been thinking about those women as Memorial Day approaches. Their decision to expand the notion of whom they chose to remember lies at the heart of what Memorial Day should be about. For those women in Mississippi, the Union soldiers, enemies in a war that divided not only a...