Despite what people would probably guess, the United States has more industrial capacity than ever.
According to this graph it's doubled in the last 30 years in fact: [click to embiggen]
from this website
Although it's Federal Reserve data, it doesn't say how exactly the capacity is quantified. I would assume it's something like the value of the products if the factory/mines/businesses ran at full blast.
The thing is--which is stuff we've talked about in engineering classes--is that innovation, making things more efficiently with better tools, and automation, such as robots and computers, have been reducing the number of jobs much more than outsourcing ever has.