There are some basic ideas that you don't actually need a Ph.D. to understand. (I have one, actually, but maybe that doesn't help.*) What the New York Times and CNN need to understand is that they do not need to and in fact cannot understand or explain the rationale behind the actions of Donald J. Trump because he is simply a deranged idiot and there is no rationale.
So. The reason some goods are imported into the United States, in general, is that the people (mostly corporations actually) who buy them find that what they want to buy is available at the most desirable combination of quality and price from foreign producers. It may not be available at any price from domestic sources, at least not in the quantities demanded in the U.S., but we'll put that complication aside for now. Note that since the last purely Communist regime on earth is North Korea, and we don't import anything from them, we are not buying from governments but from private, for-profit corporations. Canada, and Europe, are not "ripping us off" because their business corporations are selling stuff to our business corporations, which freely and voluntarily choose to buy it because that's where they are getting the best deal.
This does mean, obviously, that U.S. workers are not being paid to make that stuff, but it also means that U.S. consumers are getting the best possible deal. That's the whole business model of Walmart -- use their buying power to squeeze the lowest possible price out of suppliers, mostly foreign. Because foreign suppliers are competing with each other, and perhaps also to some extent with U.S. corporations, they are forced to sell at fair prices. Note that in competitive markets, prices are inexorably driven down to the marginal cost of production. Companies try to make a bonus by advertising and branding, to persuade people to pay a little more than the product is really worth, and there are other peculiarities of consumer behavior that make that statement a little too sweeping, but it's usually close to being true.
So, a tariff is not a tax paid by the exporting company or its government. It is a tax paid by the buyer, e.g. Walmart, on the imported good. Since Walmart is competing with Target and Dollar General and so on, they are already making a very thing margin, so if the product costs them more, they have to raise the price to the consumer, and that is who pays the tax. It is true that in the long run, if imported goods are more expensive, that can give U.S. producers an incentive to start making the thing here, or to make more of it, because they can now get a higher price. However, that will take a long time -- factories don't get built overnight -- and it may even be impossible. You need to have workers and managers with the right kinds of skills, you may be far from sources of needed raw materials which may still need to be imported, but now they're more expensive, you may need technological capacity that has to be imported and ditto about that . . . .
So, in general, the reason international trade happens is because it enables people all over the world to get the best deals on the stuff they want to buy. From the consumers' point of view, that's pretty much straight ahead. From the workers' point of view, not necessarily. One reason imported goods can be cheaper is because workers in China and Mexico and Vietnam are paid less than American workers, and to the extent U.S. producers need to compete, that can push down wages in certain industries. This in fact has happened in the U.S., as everybody knows. The kinds of low-skilled factory jobs that used to give high school grads a shot at a two car garage and a white picket fence are now scarce. This does not really pertain to trade with Canada and Europe, however. That's not why we buy buy Parmesan Cheese and Swiss watches and Quebec maple syrup, and it's not why there are auto parts manufacturers in Canada.
On the other hand, it means that people in China and Mexico and Vietnam now have money to buy stuff from us, and Europeans and Canadians have dollars to spend in the U.S. as well. And they do. Foreigners buy a lot of services -- business consulting, technical expertise, patent licenses -- and whiskey and grain and pharmaceuticals and yes, cars. Also high tech medical and scientific equipment. Even petroleum, of which the U.S. is a net exporter. Of course, it's mostly more highly educated and skilled workers and professionals who benefit from this. So yeah, some people are, rightly enough, feeling left out.
So what happens with these massive, indiscriminate tariffs on products from all over the world? First of all, they are paid, 100%, by U.S. consumers. This is the most massive, regressive tax increase in history, and it's mostly going to hurt people with less money, because a higher percentage of their income goes to buying basic goods. After a few years, it might mean that there are a few more manufacturing jobs in the U.S., but they might not pay very well because the employers will be paying more for steel and aluminum and copper. Because other countries will (and already) retaliate, it means farmers won't be able to sell their grain and distillers won't be able to sell their whiskey. Because people will have to spend more on everything they buy, they'll buy less, which could very well mean that the number of manufacturing jobs in the U.S. will decline, not increase. Meanwhile people's retirement savings are wiped out and they can't afford to send their kids to college.
So why is Trump doing this? Simple. It's because he is an insane idiot. That's the whole reason.
* More specifically, I have a Ph.D. in Social Policy, for which I had to pass qualifying exams in economics, political science, and sociology. Of course what that actually means is that I have been indoctrinated by the International Globalist Conspiracy, led by George Soros and the Elders of Zion, into the Satanic conspiracy of science. Oh, and I got the degree from Brandeis University. Aha!