Actually, we have quite a few. Just about any industry you can name with factories in the US is looking to expand in China. When you pay people pennies a day, it looks very attractive.
Funny you mentioned textiles. There used to be a lot of places that made textiles, but they couldn't compete against slave labor.
And yes, unemployment is low (although the methods for finding it, like inflation, are always changing), and that is part of the reason we have so much illegal immigration going on.
Not the same thing as slave labor. The point is people are not not working in this country.