There’s still much we don’t know. Negotiations with two of the largest U.S. trading partners, China and Mexico, are pending. For the agreements that have been announced, many terms are vague, unenforceable or incomplete. Important technical issues, such as rules for determining where an imported product comes from or whether it qualifies for an exemption, haven’t been published. Several “national security” tariff investigations are still underway. Federal courts haven’t finished considering whether Trump’s “emergency” tariffs are legal. And, while there are some early signs of the tariffs’ effects, it’ll take years before we know the details.

But here’s what we do know: As of today, U.S. tariff rates are at levels not seen in a century, which will result in hundreds of billions of dollars in new taxes paid mainly by American companies and consumers. Trade policy remains uncertain; the U.S. tariff system has gone from simple and transparent to an impenetrable labyrinth of new requirements that will prove particularly costly for smaller American businesses that can’t afford either pricey lawyers and accountants or high tariff bills and fines for noncompliance. And Trump has done it all in mere months and with zero input or approval from Congress — the branch of government with actual, constitutional authority over U.S. tariff and trade policy.

In Trump’s and his supporters’ eyes, this all constitutes a big win. The law, economics and history suggest otherwise.