In Saudi Arabia, political and religious powers are closely linked. How and why has this absolute monarchy spread Wahhabism around the world in recent history? This religious doctrine, regarded by other currents of Islam as sectarian and dangerous, sometimes flirts with radical jihadist movements. But the presence of Islamic fundamentalism within the regime has never prevented the West from placing Saudi Arabia at the centre of all its alliance strategies in the Middle East. Singled out for having created the conditions for the jihad, it remains a key ally of the Western powers.