For four decades the United States has actively pursued a trade policy designed to put manufacturing workers directly in competition with low-paid workers in the developing world, while largely protecting doctors and other highly paid professionals. It has also sought to impose longer and stronger patent, copyright, and related protections on our trading partners, as it strengthened these protections at home also.
The predicted and actual effect of these policies is to redistribute income from the less-educated (those without college degrees) to more educated workers and owners of capital. Not surprisingly, many of the losers from this pattern of trade are unhappy about it and have sought paths to change it. This was one reason many less-educated workers voted for Donald Trump for president.
While the basic facts in this story are pretty clear, the NYT seems confused about them. It told readers:
"People here embraced Mr. Trump’s anti-trade message, including his vow to withdraw from the North American Free Trade Agreement and punish China, even though Canada, Mexico and China are Iowa’s three largest foreign trading partners. They did not mind if Mr. Trump opposed increasing the minimum wage and expanding access to health care."
It is not clear what is supposed to be meant by "even though" in this context. People in Iowa would not be hurt by trade with countries if its economy was not actually involved in trade with the countries. If a manufacturer in Iowa gets many of its parts from Canada, Mexico, or China then it could be displacing workers who might otherwise be employed in Iowa. If manufacturers located in Iowa had no trade with these countries, this would not be the case. It is precisely because Iowa's economy has been exposed to trade with these countries that its workers could end up as losers.
It is also worth noting that Trump promised to offer a better health care plan in his campaign, with lower deductibles, premiums, and co-pays. Iowa's voters might have been more aware of the fact that he was lying if the NYT and other news outlets had spent a bit more time talking about health care and less time on Hillary Clinton's e-mails.