Before Oil, How Did Islamic States Get Rich?

Saudi Arabia, Iran, Iraq, the United Arab Emirates, Kuwait and Libya are all among the world’s top oil producers, and mega-rich oil sheikhs have been a fixture of the international cultural landscape for decades. But there were wealthy and powerful Islamic states before anyone had need for massive quantities of petroleum, and the way that they became wealthy and powerful should make Western political leaders think carefully about their foreign and domestic policies. Not that they will actually do so, of course.