Skad, labor makes no difference whatsoever. If you can't afford labor, you downsize. It's as easy as that, or you lower your labor costs and thus the quality of your product. No one is stupid enough to make a car that costs less than the materials and labor it took to make it.
American workers get payed more than their Japanese equilvalents though.
The American workers earn on average about $55,000.
The Japanese Nissan employees earn $41,147.64.
Remember that a lot of Japanese cars that are sold in America are also made in America. So the Union argument is already extremely weak.