However, I think you might be conflating two issues. A country can have a very high incarceration rate without imprisoning a single innocent: that country could have a very high crime rate, or the bar for "crime" could be lower and more aggressively pursued. I think the vast majority of the US' "over-incarceration" can be attributed to those two factors, not to the US just throwing randoms in prison.
Do we also sometimes imprison innocent people? Absolutely. But so does every country. As far as I am aware, there is nothing unique to the US justice system that would cause a higher incidence of actually innocent people going to jail. But we do send more people to jail. But the vast majority of them are guilty of their crimes, the question is really "should smoking pot be an imprisonable offense?", or similar.