Interesting article (old but nothing has really changed) on the social-cultural reasons why Arabic societies - militarised and clan-based - do not produce effective armed forces. We see the same thing today in attempts to construct a viable national Afghan army (to a western model).
Here's the background.
"The author, a retired U.S. Army colonel, draws upon many years of first-hand observation of Arabs in training to reach conclusions about the ways in which they go into combat. His findings derive from personal experience with Arab military establishments in the capacity of U.S. military attaché and security assistance officer, observer officer with the British-officered Trucial Oman Scouts (the security force in the emirates prior to the establishment of the UAE), as well as some thirty years of study of the Middle East."
Read the article.