Back in the 17th century, the heyday of mercantilism, most European nations had absolute monarchies, and even those that didn’t granted monopolies on foreign trade to wealthy, well-connected companies that were effectively arms of the state. Under those conditions, mercantilism makes sense. If you don’t believe me, ask Xi Jinping.
But America and its allies–to the extent it still has any–don’t meet those standards. In liberal democracies, individuals, not the state, are the primary economic actors; the state has no economic interests separate from those of their citizens. As a result, mercantilism for us makes no sense whatsoever.
To put it another way, when Trump says America is getting rich because it is taking in millions in tariffs, what good does that do for you? How does it possibly benefit you if American tax money is going into a federal government fund that won’t be spent on you?