A few years back, a friend bought me Bernard Lewis’ “What went wrong” and asked me for a review. This is somewhat late – but you might find it interesting.
Lewis’ starting points seem obvious: is the 13th century, Islam was the future. The Islamic centers in Mesopotamia were the peak of civilization. 700 years later, Islamic Mesopotamia is poor and sordid.
He is searching for an answer in culture. That seemed weird to me. Culturally, the east – and especially the Islamic east – was not a lethargic culture.
And I think I have a better explanation now.
Weatherford, Jack (2004). Genghis Khan and the Making of the Modern World (review). New York: Crown. ISBN 0-609-61062-7.