As of 2010, the US census reported there were 336,000 factories operating in the USA.
12.5 million Americans work in manufacuring, and they produced over $1.8 trillion worth of goods in 2010.
Manufacturing productivity has skyrocketed over the past 10 years thanks to technology. We are able to produce more goods with less workers.
The key part of your argument.
And census or no census, steel, textile, automobile, electronics, etc. manufacturing is gone. How many 'Made in America' labels have you seen lately?