They're wrong: it's Peter Navarro.

Navarro, for those who aren't familiar with him, is Trump's trade guru. He's the author of books such as Death by China, The Coming China Wars and China: Why Don't We Just Nuke 'Em? (only one of these is made-up). He's also been described as selling "dodgy economics", "alarmingly ignorant", "astoundingly ignorant", "misguided" and "dangerous".

Navarro's basic idea is that countries such as China, Japan and Germany have rigged the trade system against the US. Their large export surpluses are the result of currency manipulation and other underhand tricks.

More broadly, the Navarro-Trump view is that exports are good and imports are bad. The goal of America's trade policy should be to maximise the former and minimise the latter – that is to say, it is more important to eliminate trade deficits, whether with individual countries or the world as a whole, than it is to grow trade volumes.