You make a good point, that outsourced jobs and losses to efficiency gains have to be considered together. Also, as you point out, individual industries differ in their mix of the two factors. I don't know whether there are good studies that integrate the two forces; I would assume there are, but maybe not for manufacturing as a whole, say. Some basic manufacturing is returning to the US as a result in leaps in process efficiency in steel, for instance. Meanwhile, as an example, logging and mill jobs, which aren't practically outsourced, have decreased greatly due to CAD/M and mechanization, and won't come back.

There is job loss and there is perceived job loss. Pittsburg lost its smelters, Akron lost its rubber, New England lost its looms, Philadelphia lost its locomotives. Those jobs were outsourced long ago. In addition, private sector unions have lost their power to raise wages. 

In the short term, job stimulus would give a big boost to the US economy, before other jobs return.