Under pressure from far-right factions, European Union politicians blamed Spain for the mass crossing at its border with Morocco last week. Their reaction missed the larger human tragedy at play, say migration researchers.

About 75 migrants died during the crossing, while the EU blamed smugglers and false information for encouraging the surge.

More than 70 people died after thousands of migrants tried to cross from Morocco into the Spanish exclave of Ceuta. The crossings have been linked to misleading claims about a…