Answer:
Because so many people were getting addicted and it created a problem in china
Explanation:
<span> The Mexican/American War was an armed conflict between the United States and Mexico that took place in 1846–1848. However, Mexico
refused to accept these as valid, claiming the border was the Nueces
River. U.S. President James Polk endorsed the Rio Grande boundary, which
incited a dispute with Mexico.
I hope this helped:)
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