Why were the Ottoman and Qing Empires vulnerable to Western pressure in the nineteenth century?

There were a number of elements that made both the Ottoman and Qing Empires vulnerable to western influence and pressure during the 1800s. These ranged from political corruption, changing social norms, and weakening militaries. One thing that both empires shared though, were lopsided trade treaties known as capitulations.
In the case of the Ottoman Empire, capitulations, which began in the 15th Century, were trade treaties with Christian powers which guaranteed foreign merchants in Turkey certain favorable concessions. Notably, these merchants would only be subject to the laws of their country of origin. They also imposed very modest import duties on foreign trade while allowing the western nations to impose hefty export taxes on Turkey. Foreign powers were even able to establish banks and houses of commerce in Turkey that were completely exempt from local taxes and regulations. As these capitulations continued throughout the 1800s, western powers found it easy to influence the markets and economy of the Ottoman Empire to their advantage.
This situation was much the same in Qing Dynasty China. The "Unequal Treaties" of the 1800s forced the Chinese to establish what were known as treaty ports. In these port cities, foreign merchants were able to operate completely outside of Chinese law. Foreign traders and financial institutions were able to bring in massive amounts of foreign goods and flood the Chinese market with them. The Chinese were unable to do much to combat this outside influence. Indeed, they tried and failed during the disastrous Opium Wars. Like the Ottomans, they lacked the military strength and economic might to be an effective foil against Western pressure.
All these erosions of local sovereignty made it inevitable that China and the Ottoman Empire would be vulnerable to western pressures. Without strong enough militaries to counter these capitulations and one-sided mercantile arrangements, the two empires were stuck with having to deal with the intrigues and influence of western powers.
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