Denied a military parade in Washington, President Trump sought one abroad. In Paris, on the centennial of Armistice Day, he found not the jubilant flyovers, ribbons, and uniforms that he had perhaps envisioned, but a solemn procession and ceremonies that highlighted war, not in its glory but its sacrifices.

At cemeteries and monuments framed against a gray sky, the events commemorated the young men who taught the world a lesson twice. They paid in blood for the bitterness of division and the failure of an agreement that was meant to end the violence but paved the way for more.