He has brought up before that the US government used to get its revenue from tariffs before income taxes were introduced.

The US is running ginormous deficits but their religion doesn’t allow them to raise taxes. So this might be his least bad option (talking about his internal politics, not the actual economics) to start addressing his deficit.

This worked once, way back in the 19th century. It hasn’t worked since.

Not to mention that they got a massive trade war at the time as well, and seriously strained their international relations. But back then, the US was a nobody nation and nobody cared about them, so going from “nobody” to “annoying joe shmoe” wasn’t a problem. Now everybody watches carefully to see how the US rolls over even in its sleep, so every little thing they do on purpose has a huge rippling impact.

They’re not only starting a trade war when nobody has won a trade war in over a century, but they’re destroying a century of built up trust in the meantime, and economies are built on trust. Without trust, who the hell is willing to sign a deal that lasts more than a few months when the norm is to sign decade long deals?