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.

although world war i began in 1914, the united states did not join the war until 1917. the additional firepower, resources, and soldiers of the u.s. to tip the balance of the war in favor of the allies. remaining neutral. when war broke out in 1914, the united states had a policy of neutrality.