After World War I, when Britain and France divided up the Middle East's countries, apart from Turkey, between them, pursuant to the Sykes-Picot agreement—in violation of solemn wartime promises of postwar Arab autonomy—there came an immediate reaction: the Muslim Brotherhood emerged in Egypt, the House of Saud took over the Hijaz, and regimes led by army officers came to power in Iran and Turkey. de Bellaigne attributed the growth of Islamism and militarism to what Western catalyst?