I would also note that as the American public is currently discovering, there are far more children working in slaughter houses, factories etc than they thought. And this doesn't even include things like the troubled teen industry which runs work camps for teens who often haven't committed a crime or juvenile prison labour.
You also have the fact that several US States are currently passing or pushing bills to re-legalise children working in these dangerous places. So you have all of China pushing in anti-child labour direction and a significant proportion of the US pushing in a pro-child labour direction.