US stats include people who spend a few days in the county lockup. (This data is usually unavailable from other countries). The US reports stats honestly unlike places like China and North Korea. The discussion usually complains that minor drug offenders are jailed and that black citizens are overtargeted. Only 1/6th of the state prison population is in for drug offences, mostly for dealing. The black prison population is 40% of the total but if only killers were jailed, that number would rise to 50%. This information is culled from Paul Mirengoff's article, "The Myth of Over-Incarceration".
Still, the numbers are large.