How did the opium wars lead to the downfall of imperial china and lead to the future civil war

In addition to the drain of silver, by 1838 the number of Chinese opium addicts had grown to between four and 12 million and the Daoguang Emperor demanded action. Officials at the court who advocated legalizing and taxing the trade were defeated by those who advocated suppressing it. The Emperor sent the leader of the hard line faction, Special Imperial Commissioner Lin Zexu, to Canton, where he quickly arrested Chinese opium dealers and summarily demanded that foreign firms turn over their stocks with no compensation. When they refused, Lin stopped trade altogether and placed the foreign residents under virtual siege in their factories. The British Superintendent of Trade in China Charles Elliot got the British traders to agree to hand over their opium stock with the promise of eventual compensation for their loss from the British government. While this amounted to a tacit acknowledgment that the British government did not disapprove of the trade, it also placed a huge liability on the exchequer. This promise and the inability of the British government to pay it without causing a political storm was an important casus belli for the subsequent British offensive.

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