摘要：Think of all the American industries that once flourished and now are gone or virtually so. Copper mining in the southwest; gold mining in California, South Dakota and Alaska; the timber industries of the East Coast; the fishing industries along many parts of both coasts; and the steel industry of the Great Lakes region. Each of these industries once was the central force in some local or regional economy. Now each of them has vanished to some degree. All that is left of the copper mining that thrived in Arizona during the late-1800s are a scattering of ghost towns. Gold mining in California has left behind only a few hobbyists and numerous museums. The steel industry has mostly rusted into memory. In their heyday each of those industries caused inward migrations of workers to the regions, triggered large-scale investments in economic activities of many sorts, and fueled the economy of the surrounding region. Each of those industries was proud, productive and profitable … in its prime.
