Washington is filled with memorials that are sobering reminders of our past, and we can’t visit these sights without responding in some way — whether in gratitude for sacrifices made or sorrow over tragic loss. This week, I visited a new memorial as it made a temporary stop in D.C. Like other memorials in this city, you cannot visit this one without being moved to respond, but this memorial does not just look to our past. It is a sobering reminder of our present.

The...