After the Civil War ended — which took more American lives than all of our other wars combined — the men, women, and children who remained didn’t know how to respond. The ~750,000 losses were unfathomable . . . numbing, in fact. In that aftermath, just about the only response was to acknowledge the grief. In the years immediately after the conflict, that remembrance took the form of decorating the graves of fallen soldiers, which eventually morphed into a federally recognized Memorial Day.