If you live in California, it's at least five years before you can get past most environmental impact statements, convince local governments that you're really going to benefit them economically, get appropriate blessing from various air quality mangement districts, and break ground. The regulations are very imposing. Add to that the new CO_2 regulations in CA, and one can get into a real nightmare.
Consider solar energy plants in the high desert -- lots of land, lots of sun, lots of panels. No way to get the energy back to the consumer because as soon as a shovel hit the dirt, environmental groups sued over the transport lines that would have to cross the desert back to population.
Although I'm not entirelt convinced that labor costs are small in comparison to total product cost. Lee Ioccoca pointed out that even in the 90s, Blue Cross became Chrysler's #2 supplier. It's those indirect costs of labor (approx. 2.5x salary) that eventually make US manufacturing unappealing.