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Madrid–Outgoing Socialist Prime Minister Jose Luis Rodríguez Zapatero, of Spain, had until recently been the beneficiary of propitious circumstances. Party infighting enabled him to outmaneuver the establishment favorite in the 2000 primaries. Four years later, he eked out an eleventh hour victory in national elections when a terrorist bombing mere days before voting turned the tide against incumbent conservatives. As he took office, a booming economy—which enjoyed the second largest budget surplus in Europe as late as 2007—paved the way for an ambitious social agenda, which rallied his progressive base.

But if a flair for the unexpected studded his ascent, it was a bruising inevitability that brought him low. A rapidly worsening economic crisis...