but it turns out steve boehne was ahead of the curve, or at least ahead of most economists, who have argued since adam smith that trade is the key to economic growth by spurring competition and thus lowering prices, and arguing that in our era, technology replaces jobs, not cheap foreign labor. >> but as we went into the 2000s, with the rise of china, the situation changed.t >> reporter: it's what economish gordon hanson learned from a soon-to-be published academic study he co-authored: that chinese imports really did hurt u.s. wages and employment, but selectively. >> what we were surprised by was that those effects were not distributed kind of broadly and evenly across blue collar workers in the united states, but really concentrated on industries and workers and communities that produce goods that compete in the same arenasi that china does. >> reporter: clothes, furniture, low-end electronics, in blue- collar strongholds and keyco battleground states likett pennsylvania and ohio. >> those workers in those regions are the losers of globalization in the unitedse states. >> reporter