The citizens of Madrid poured into the streets to grieve on Friday. In the aftermath of last week’s calamitous bombing of a train in Madrid, an estimated 12 million people throughout Spain came together to cry out against the violence of terrorism. Thursday’s attacks were a grievous horror; 200 killed, 1,400 wounded. Slaughter of this magnitude causes emotion of inexpressible depth—made all the more upsetting because only now have investigators learned who was responsible and what their motive was. What happened in Madrid was so atrocious as to seem inhuman, and yet the world is faced with the difficult realization that such disastrous destruction could be, and indeed was, man-made.

The heartwarming, global response to the terrorist attacks in Madrid is reminiscent of the worldwide outpouring of sympathy in the weeks following Sept. 11, 2001. Since then, the controversy over American engagement in Iraq has stimulated deep divisions in the international community. For too long, these divisions have overshadowed the broader tasks at hand and the reality that all nations remain vulnerable. Devastating terrorist attacks have occurred not only on American soil, but also in Bali, in Istanbul and now in Spain as well. The great question of how to stop global terrorism is still unanswered.

The revelation yesterday that al Qaeda was likely responsible for the attacks—instead of militant Basque separatists as initially reported—brought little clarity, just more confusion to a world already bewildered and tense. Top American officials yesterday insisted that the latest attacks would not shake Europe’s resolve. Secretary of State Colin L. Powell said on television that the Madrid attacks mean anti-terror efforts ought to intensify, not diminish: “There is a war on terror that must be fought. Nobody’s immune.” Still, many protestors have blamed the attack on the government’s support of the Iraq occupation, and yesterday’s surprising election results ousting the ruling Popular party from power signals more changes are potentially in store.

This discussion is healthy. If a war on terror must be fought—how it ought to be fought remains to be fully understood. President Bush said in January that the invasion of Iraq had made the world a safer place; Thursday’s bombing, if nothing else, should generate pause. Much work lies ahead.

Families in Madrid have begun the task of mourning the loss of their loved ones in Thursday’s senseless violence. We are reminded that each of the victims was somebody’s mother, father, spouse or child; in the words of one Spanish banner, “we were all on that train.”

We stand in solidarity with the millions who turned out in Spain to protest terrorism on Friday. With arms outstretched and palms facing upwards, they declared in no uncertain terms that the violence must stop. In the midst of our grief for what happened, our most sincere hope extends out to the prospect that this violence will end. We are with the people of Madrid in these hours, as they bury their dead and grieve. And we look ahead at the difficult struggle that remains.