What was the cause of the opium war in 1839-1842?

Between 1839 and 1842 British forces fought a war on behalf of drug traffickers. Their victory opened up the lucrative China trade to British merchants. This was all done with the full blessing of the British government.

in 1803 the louisiana purchase took place, doubling the size of the country. by 1840 almost 7 million americans had migrated westward in hopes of securing land and being prosperous. the belief that settlers were destined to expand to the west is often referred to as manifest destiny.

explanation:

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