Trump’s Tariffs Follow Anger Over Trade Imbalances and Lost Manufacturing Jobs

President Trump upended the international trading system on Wednesday with a blunt package of global tariffs, making the case that the United States faces a dire economic emergency as a result of trade imbalances with countries across the globe.

It’s a sentiment that Mr. Trump has expressed for decades, one that helped propel him to the presidency amid anger over lost manufacturing jobs and widening trade deficits. While the United States has the largest and strongest economy in the world, Mr. Trump — and many of his supporters — have long held the view that America has been ripped off by other countries and that tariffs are the answer to rectify decades of what they call unfair treatment that has shuttered factories, decimated communities and hurt workers.

“Every prediction our opponents made about trade for the last 30 years has been proven totally wrong,” Mr. Trump said on Wednesday, pointing to trade deals such as NAFTA and the Trans-Pacific Partnership as well as the tariffs he imposed during his first term. “We can’t do what we’ve been doing for the last 50 years.”

Since his days as a real estate developer in the 1980s, Mr. Trump has been railing against the trade and business practices of other countries that he found to be unfair. Back then, when Japan was a booming economic rival, Mr. Trump used to assail its tactics.

“If you ever go to Japan right now, and try and sell something, forget about it, Oprah. Just forget about it,” Mr. Trump said, in a 1988 interview with Oprah Winfrey, adding, “They come over here, they sell their cars, their VCRs, they knock the hell out of our companies.”

This week he made good on his promise to try to force more companies to make their products in the United States. He punished trading partners with stiff tariffs, despite anxiety from economists, investors and businesses that his approach could send prices soaring and tip the economy into recession.