Note that the statistics only count the most serious of the offenses for which the person was sentenced, which means that some of the violent offenders may have also been charged with drug crimes.
Suppose every violent crime has a sentence of one year, and every drug crime a sentence of five years. You'll retain drug inmates and lose violent inmates, quickly yielding a situation in which there are more drug inmates than violent inmates.
(This is simply to demonstrate a logical contradiction in your proposed evidence, and is not intended to make a factual argument.)
It's not kosher to complain about a downvote, but this is a logically sound and complete demonstration of why the evidence posted above doesn't actually support the purported claim. It indicates, yes, but it is in no way, shape, or fashion proof. I'm not sure how a correction is liable for downvotes.
If so I'd have to dispute it. I do think the U.S. imprisons too many people for drug charges but I also think China and Russia have a lot of people imprisoned "off the books". Also keep in mind the statistics don't tell the whole story. We all know Russia doles out a lot of punishment via hit squad and China, who won't release their capital punishment numbers, admits to executing more people than any other country on earth (though not per capita thanks to Iran)
If China has fewer people in prison because the execute far more people than your argument isn't really a valid one
China executes at most a rounding error of the US prison population. 2005's high of 10,000 is less than half a percent of the current US prison population, and they would need to have been performing at that high for seventy years to hit the US population. Furthermore, they have a billion extra people! Nowhere close to the American rate(!) of imprisonment. (They'd need approximately five times as many their official imprisonment rate 'off the books' to equal US.)
IIRC, even China doesn't have as many people in jail as the US.