> I’m sure I’m way over simplifying this, to the point of stupidity This is, to an extent, the problem, yes. There are plenty of problems, but here's one very

> I’m sure I’m way over simplifying this, to the point of stupidity This is, to an extent, the problem, yes. There are plenty of problems, but here's one very obvious one; your own industry almost certainly depends heavily on imports, particularly if you're a developed country. If you basically only have primary industry, then this sort of protectionism can _theoretically_ work and allow development of secondary industry (though in practice there aren't many examples of this), but for a developed country it really makes very little sense. You're also assuming that local industry _will_ compete on price, versus just accepting the newly-set tariff-induced base price. That will happen in some cases, but not all; in particular for near-monopolistic industries (cars, a lot of heavy consumer goods like kitchen appliances), really, it makes a lot of sense for them to raise their prices under such circumstances.