Free-trade critic Ian Fletcher argues that the United States has too little manufacturing. Even if manufacturing output is at an all-time high, he argues, it's still too low. So clearly he has in mind some amount of manufacturing that is right or, at least, some criterion by which we can judge whether the amount of manufacturing is the right amount. Here's his criterion:
Unfortunately, the only rational standard for how much America should produce is how much Americans wish to consume. Because the only way to consume is either to produce what you wish to consume, or produce something else you can exchange for it. (italics in original)
If we take this literally, we are producing enough.