First came the disintegration of the Ottoman Empire following World War I; then, in the 1950s and '60s, the Nasser-inspired wave of Arab nationalism and socialism. The Arab world's third great political cataclysm of the past 100 years has also brought permanent changes, but not as its activists had hoped: the 2011 uprisings.
Their consequences have differed greatly from area to area, splintering the Arab region into four different worlds. The Levant...