From the linked Article:
imports of opium (to the United States) increased from around 113,000 pounds in the 1840s to 1,500,000 pounds in 1909
Opium was legal in the USA for centuries, and use never got anywhere near China levels.
“Genetic factors account for about half of the likelihood that an individual will develop addiction. Environmental factors interact with the person’s biology and affect the extent to which genetic factors exert their influence. Resiliencies the individual acquires (through parenting or later life experiences) can affect the extent to which genetic predispositions lead to the behavioral and other manifestations of addiction. Culture also plays a role in how addiction becomes actualized in persons with biological vulnerabilities to the development of addiction.” - American Society of Addiction Medicine
This is a statement I *ALWAYS* hear from someone who has not done the proper degree of research as to the American History of Drug usage and exposure.
In the early stages of this nation, there was little access to the stuff, and most people considered it to be a medicine. Nobody was shipping tonnage amounts of this stuff into our harbors. When it arrived, it was in a few bottles and those relatively small in number.
The Civil War changed everything. The Wounded in the Civil War on both sides could have their pain alleviated with Opium and Cocaine, and both sides sought to get as much of the drug as was possible. In the aftermath of the Civil War, both the North and the South ended up with hundreds of thousands of wounded men who were now addicted to Opium and Cocaine. (But mostly Opium.)
Addiction among service men became so common that they started referring to it as "The Soldiers Disease."
Add to this efforts by companies such as Coca Cola to supply Cocaine in their soft drinks, and by the 1890s, people were noticing a lot of serious problems caused by these drugs.
The Difference between the US and China is that China already had much history with Opium, and they had large supplies of it in their own country and being brought in by the British. As the addiction habits in the US were growing worse, suppliers were stepping into the market to fill these demands. Given enough time, we would have gone down the same road as China. Fortunately the Federal government stepped in, banned the substances, and stopped this addiction epidemic before it got much worse.
From the linked Article:
imports of opium (to the United States) increased from around 113,000 pounds in the 1840s to 1,500,000 pounds in 1909