How did western powers use diplomacy and war to gain power in qing china

Opium wars and harsh demands.

Explanation:

Western powers used diplomacy and war to gain power and Qing China by beating the Chinese in a series of Opium wars then making demands that the Chinese must comply with. After every war the demands would become increasingly harsher. ... The Qing dynasty had an uprising by its own people called the Boxer Rebellion.

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