In short, the rust belts have been killing the goose that lays the golden eggs. That is a viable political strategy, so long as the goose doesn't die before the next election and politicians can avoid leaving their fingerprints on the weapon.
But the people who lose their jobs, and who live in communities that decline, need to look beyond the political rhetoric to the grim reality that there is no free lunch.
Many workers in the new plants being built by Toyota and others apparently already understand that. They have repeatedly voted against being represented by labor unions. They want to keep their jobs.
Where does NAFTA come into the picture?
International trade is just one of the many ways in which the competition of lower cost producers can cause higher cost producers to lose customers and jobs. Technological improvements or better management practices by domestic competitors can have the same result.
Jobs are always disappearing. The big question is why they are not being replaced by new jobs. Rust belt policies that drove out old jobs also keep out new jobs.
NAFTA makes it easier for politicians to blame the problem on foreigners. In fact, foreigners make ideal scapegoats for politicians. After all, people in Japan or India can't vote in American elections.
Americans who can vote would do well to start spending more time thinking about economic realities, instead of being swept away by political rhetoric.