Todd Tucker is a political scientist and fellow at the Roosevelt Institute. He is author of “Judge Knot: Politics and Development in International Investment Law,” out this spring from Anthem Press. Follow him @toddntucker.

After roiling markets Thursday by floating steep steel tariffs, President Donald Trump doubled down with an early-morning Friday tweet claiming “trade wars are good, and easy to win. Example, when we are down $100 billion with a certain country and they get cute, don’t trade anymore-we win big. It’s easy!”

The tweet was characteristically Trumpian: Confrontational, vague on details, and promising to solve one of the world’s most complex problems through simple toughness. And by so casually invoking a “trade war,” it turned the previously unthinkable—an actual escalating trade conflict with our key economic partners—into something approaching U.S. policy.


Is he really about to wage a trade war – and if he is, could it really work? If there’s anything that trade history tells us, it’s that Trump’s tweet is by turns unclear and untrue. Trade wars are rarely “good”; they tend to bring down both sides and produce no winners. They’re not easy, either. And the realities of underlying trade law raise another prospect that Trump perhaps should have thought of before he hit the button: The way he tweeted out his threat could work against his own goals.



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There are three big problems with Trump’s declaration. First, “trade war” is a misnomer—one that has already been thrown around, wrongly, to describe Trump’s policies before this week. He has already walked away from the Trans-Pacific Partnership negotiations, and is in the midst of trying to renegotiate NAFTA. Any country is in its sovereign right to do these things—to walk away from a trade negotiation, or to raise tariffs. Hillary Clinton shared the president’s opposition to the Trans-Pacific Partnership, which in any case appeared to lack sufficient support in Congress to be approved. And anti-dumping duties like those Trump announced on solar panels were commonplace remedies in past administrations, and based on independent agency advice. His critics are hyperbolic when they call these measures warlike just because they would prefer freer trade.

It’s even less clear why Trump himself would choose to use the war metaphor for his latest actions. In January, the Commerce Department gave Trump options to impose 24 percent tariffs on all countries, or 53 percent on a smaller set of 12 countries (including China). Trump appears to be going with the former, plus a percentage point. Is that what Trump’s labeling a “war”? If he does escalate it and broaden it to more products, that’s not a war—it’s declaring yourself an island. Even the Black Panther’s autarkic Wakanda eventually opened up to the world.

There’s an academic reason why trade conflicts get called “wars.” Under the United Nations Charter, war is considered to be an unlawful way of resolving disputes. Trade policies – even severely protectionist policies – can be perfectly legitimate. The “war” metaphor is used for policies that lie outside of international trade law. Of course, at the international level, “breaking the law” is often in the eye of the beholder, and in fact a new book by Northwestern University’s Ian Hurd argues persuasively that even countries that appear to break international rules will often argue for the legality of their own position. Expect Trump to do the same here, claiming that U.S. and international law gives them the flexibility to raise tariffs above their statutory levels.



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Second, even if we call them “conflicts” rather than “wars,” trade conflicts are never easy—and they don’t lead to winning big. So far, as we understand them, Trump’s plans are to raise tariffs on imported steel by 25 percent and aluminum by 10 percent. These are big moves that will raise prices across the economy and invite retaliation. They recall, on a more limited scale, the classic “trade wars” of the past, defined as cycles of punitive protection and retaliation. These are rare. It doesn’t make sense for small countries to take on rich countries, because they end up hurting themselves without inflicting noticeable pain on their adversary. And rich countries tend to avoid trade wars with one another, precisely because it raises costs for domestic consumers. The Anglo-Hanse trade war of 1300-1700 sounds like something vaguely remembered from freshman history class for a reason. Indeed, Al Gore won his famous debate with Ross Perot over NAFTA by implying his protectionist views were as old as the Smoot-Hawley tariff of 1930, which many scholars saw as worsening the great depression by setting off tit-for-tat retaliation.

Perhaps fittingly, the trade conflicts that did produce clear winners were the ones that actually deserved the label “war.” In the mid 19th century, by backing up their trade goals with bayonets, the English succeeded in prying open China to English goods and drugs during the Opium Wars. In the 18th century, the British were on the other end of the stick, when American colonists eager for local control of trade succeeded in routing the mother country. Today, of course, nobody is talking about deploying jets to enforce a surcharge on steel. The more predictable outcome if this trade conflicts sprawls out is lowered well-being on both sides.



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Finally—and most important—Trump’s tweets could undermine his own policies. Trump and his allies often point out that China’s aggressive market interventions to lower the price of steel already constitute a “trade war.” It’s just that no one has bothered to fight back. There is some truth to that, and a policy response of some kind is reasonable. But if Trump wants to get his steel tariffs done, he’ll need to be ready to make an argument that they’re legal under U.S. and international law.

The 400-plus pages of recommendations issued by the Commerce Department in January were tailored to help him on this score. Under Section 232 of the 1962 Trade Expansion Act, Congress gave the president license to pursue a forward-looking industrial policy in the name of geopolitical strength. Indeed, the law explicitly allows him to take action to preserve the wellbeing of industries even when they’re not injured under the traditional trade law definitions. All the Supreme Court requires is a process that shows the executive branch took the statutory documentation requirements seriously.

Trump’s erratic tweets and comments are going to make life harder for his administration’s lawyers when these rules are challenged, as they almost surely will be. So far, he has suggested, at various times, that the purpose is to close bilateral deficits, to save domestic industries, and simply to match foreign tariffs tit-for-tat—a range of motives so wide that it suggests the policy is really driven by an underlying anti-foreign animus, rather than a careful consideration of the nation’s economic objectives.

We’ve been here before. Last year, when Trump’s travel ban was repeatedly rejected by courts, a big part of the reason was Trump’s own comments about it. Nobody contested the president’s legal powers to police American borders and keep the country safe. But numerous judges flagged Trump’s tweets about the policy, and about Muslims, as evidence it was driven more by bias than by legitimate security interests.

Trade policies face similar legal constraints both domestically and internationally. WTO rules allow for countries to deviate from their trade obligations for national security reasons. The body has never issued a ruling clarifying the boundaries of this right. And arguably the Commerce Department report could help Trump pass the test, if it’s used in conjunction with a convincing argument that the WTO’s failure to discipline Chinese state-led capitalism constitutes a crisis in international relations. Advocates for the tariffs have already begun making this argument, given the president a ready-made pathway to enforce new tariffs within the bounds of existing law.

But trade panels have at times scrutinized the intention of policymakers that are invoking exceptions. And given the historic nature of this case – and the way Trump is viewed both in Washington and internationally – it’s reasonable to expect they’ll subject his policies to that kind of scrutiny here. When they do, his shifting rationales and casual declaration of “war” for national advantage could well undermine the more careful argument that this is a legal pursuit of reasonable remedies. If U.S. courts or the WTO determine his tariffs fail to meet the correct legal tests, they could order him to get rid of them.

Even if his tariffs aren’t struck down in court, any sudden trade move could, ultimately, trigger the supreme political sanction. As legal scholar Cass Sunstein argues convincingly in his new book Impeachment: A Citizen’s Guide, maladministration of U.S. treaties and foreign affairs are clearly among the grounds the founders envisioned for impeachment, even when no law is violated. The impeachable acts of “high crimes and misdemeanors” don’t have a formal definition, but if we follow Sunstein’s reading, presidential actions that are legal but nonetheless “atrocious” or that harm the interests of the country as a whole would surely fall into that category. This prospect is far off, and surely depends on a lot more going wrong in the meantime—but it’s not unthinkable that this president could find that in this new “war” he’s declaring, the main target of hostilities ends up being him.