answer is simple : poverty and backwardness but there are/were similar violence in balkan states..

BTW, The borders between M.E. states were artifically drawn by Brits with the aim for future problems (Just like Balkan states). In this way these oil rich states would never be trouble free, never self sufficient and Brits could interfere easily. For ex. Iraq had sunni rule despite to shia majority, Syria has a Alewit rule despite to sunni majority etc.. so these states could never find an oppurtunity for progress, they always spent their energy for interior problems..
Another problem, after ottomans, the vacuum in Cacausia, Balkans and Middle East wasn't full completly by a stable power, it was only frozen by communism in cold war era... same applies to some asian regions (Afghanistan, Kashmir) which were under Brit. rule for long time.

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