<span>They did it to protect their authority
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Because it expressed the fact that Americans didn't want European countries that had economic or colonists interests to put a foot in the United States.
<span>British ships began landing supplies of opium in China in the late 1700s and early 1800s, mainly around the mouth of the Pearl River in Guangdong. Opium became more available and more affordable to all levels of Chinese society, even the working classes.
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