In normal times, Donald Trump’s announcement of tariffs on $200 billion worth of Chinese goods, bringing us closer to an all-out trade war, would have dominated headlines for days. Things being as they are, it was a below-the-fold story, drowned out by all the other scandals underway.

Yet Trump’s tariffs really are a big, bad deal. Their direct economic impact will be modest, although hardly trivial. But the numbers aren’t the whole story. Trumpian trade policy has, almost casually, torn up rules America itself created more than 80 years ago — rules intended to ensure that tariffs reflected national priorities, not the power of special interests.

You could say that Trump is making tariffs corrupt again. And the damage will be lasting.

Until the 1930s, U.S. trade policy was both dirty and dysfunctional. It wasn’t just that overall tariffs were high; who got how much tariff protection was determined through a free-for-all of horse-trading among special interests.

The costs of this free-for-all went beyond economics: They undermined U.S. influence and damaged the world as a whole. Most notably, in the years after World War I, America demanded that European nations repay their war debts, which meant that they had to earn dollars through exports — and at the same time America imposed high tariffs to block those necessary exports.