I confess I do not get this from Paul Krugman.
Yes, the trade deficit crowds-out traditionally-male blue-collar import-substituting manufacturing jobs, but imports crowd-in traditionally-male blue-collar wholesale trade jobs, and finance traditionally-male blue-collar construction (and capital-goods manufacturing) jobs. If you look at all traditionally-male blue-collar—wholesale, construction, manufacturing, and mining)–what you get is not a story of the trade deficit, but rather a story of (a) macro shocks to aggregate demand, and (b) the long-run technology-and-preferences trend—some of which is automation.
NAFTA is nowhere.
The 2002-2007 bilateral-trade "China shock" is simply not a terribly big deal for the country as a whole: employment in traditionally-male blue-collar occupations was flat. A big deal for places that found their manufactures competing with new imports from China, yes. But not for blue-collar traditionally-male employment in the country as a whole.
For the country as a whole, it is aggregate demand—2001-3 recession, weak recovery, 2007-9 catastrophe, and then superweak recovery—with a supporting role for technology-and-preferences:
Paul Krugman: "Yang asserts that automation destroyed lots of manufacturing in the midwest, [but] you don't have to be a protectionist to realize that the acceleration of job loss after 2000 was mainly about the surging trade deficit: