In the interest of brevity, I'm only going to talk about China, but I think this accurately captures Trump's sentiments on the matter, and gives a good bit of background on the issues he's talking about, and his policy stance.

1/2

So, it's important to note that the US already does some of what Trump is talking about - - just not as aggressively as Trump says it should be done, both in financial levy and in the 'diplomatic manner' of communicating the US trade posture when it comes to imposing tariffs.

For instance, China - which isn't a market economy and has many State owned enterprises - often massively subsidizes its own industrial output, so that goods they manufacture can be sold at significant losses, with their central bank insulating the actual corporate entity from the massive lost profit, the intent being to "dump" these goods in markets where they want to choke out any domestic competition for their exports with products whose prices can always be cut down.

The US takes umbrage at this, because it's not just nick nacks sold at Wal Mart, but things like solar panels, steel produce, and renewable energy technology components.

One such law is the horribly nondescript Public Law 112–99 of 2012 (Yes, that's the real title, and yes, it is super lame. We can do PATRIOT Act for surveillance? but hitting back on trade gets - - well, nevermind) which imposed tariffs on Chinese goods to jack up the tax burden on those products to counter balance their dumping strategy.

Here's a Reuters article about China losing an appeal at the WTO when they brought their dispute against the US to international authorities.

China lost its bid to overturn U.S. legislation targeting unfair trade subsidies on Thursday, its second defeat in a World Trade Organization dispute within 24 hours.

A WTO dispute panel threw out China's claim that the U.S. "Public Law 112-99", signed by President Barack Obama in March 2012, broke world trade rules.

The U.S. "Public Law 112-99", also known as the "GPX fix", was rushed through after Chinese companies including GPX International Tire successfully argued at the U.S. Court of International Trade that the United States could not punish Chinese trade subsidies because China was not a market economy.

However, Froman said he was disappointed that China won another part of the case, in which the WTO ruled the United States had been wrong to punish some Chinese exports twice over - once for being subsidized and once for being "dumped", or sold at unfairly cheap prices.

And here's a very triumphant, yet sober 'government-y', press release about the same decision, put out by the USTR

China Fails A Second Time in its Challenge to U.S. Countervailing Duty Law

The GPX legislation was enacted on March 13, 2012, to confirm the Department of Commerce’s ability to apply the U.S. countervailing duty (CVD) law to subsidized imports from non-market economy (NME) countries, including China. As a result of today’s report, together with the May report from a WTO panel rejecting all of China’s claims under Article X of the GATT 1994, there are no WTO panel or Appellate Body findings that the GPX legislation breaches WTO rules.

The Obama Administration will continue to vigorously defend any challenges to the application of our trade remedy laws to ensure that U.S. workers and businesses are not put at a disadvantage by Chinese or other subsidies. The United States acted within its WTO rights in enacting the GPX legislation to confirm that duties could be applied to counteract unfair Chinese subsidies.

“Today’s decision allows U.S. industries to continue to rely on U.S. trade laws to address unfair competition from their subsidized Chinese competitors. As we closely review the impact this decision may have, the Obama Administration and the Commerce Department remain committed to robustly enforcing the U.S. trade remedy laws that allow our producers and firms to compete on a level playing field,” said Secretary of Commerce Penny Pritzker.

China has been on notice since 2006 that the United States might apply countervailing duties to unfairly subsidized Chinese imports that cause injury to U.S. workers and businesses, just as the United States does to unfairly subsidized imports from other countries.

(emphasis added)

It's a government press release, and you can put a similar situation to this in space with light sabers and robots and it's still fucking boring, but I can't help but detect a little shade being thrown in how the US Office of The Trade Representative writes about the matter.

Even policy wonks have an edge, I guess.

But the crux of the matter, is that we do as a nation do what Trump is talking about when it comes to fighting trade imbalances - - we really do impose tariffs.

The US-China Trade Deficit is currently standing at around 360+ Billion Dollars, which is to say, on the balance of stuff we buy from them, and they buy from us (them selling to us, and us selling to them), they're coming out ahead, and we're coming out behind, by around 360+ billion US Dollars each year.