[NorseViking]

Illiteracy and lack of industry are key elements. In order to be somehow successful a metropoly needs to have some appeal among constituents. Turkey lacked in cultural and economic senses and it became especially critical in the era of technologies. They went downhill starting 18th century.
Modern Turkey is still underperforming because of poor education. There are too much illiterate bums doing stupid jobs or outright doing nothing. The environment allows to absent from a rat race which they luckily do. Then they blame Arabs for taking their jobs or Russians embargoed their exports or Jews ‘directing’ all the above.

[nickcarraway]

I’m shocked you would badmouth a strong ally of Russia.

[BikerJoe]

Illiteracy and lack of industry are key elements.

Or, as P.J. O'Rourke wrote: "The Ottoman Empire, so called because it had the same amount of intelligence and energy as a footstool."