Korea shouldn’t celebrate on tariffs just yet

The Lee Jae-myung administration emerged from “pragmatic” diplomacy with a headline-grabbing claim: the United States, under President Donald Trump, had agreed to cap tariffs on South Korean exports at 15%.

Seoul spun it as a win—a stabilizing gesture meant to cool economic uncertainty. For a country with deep reliance on U.S. trade access, the announcement seemed like a shield against the chaos of Trump’s second presidency.

But look closer, and the foundation crumbles. There is no signed agreement. No formal declaration. No U.S. legal record. And already, the two sides are offering conflicting interpretations of what, exactly, was agreed to.

In typical Trump fashion, this “deal” is less about policy and more about posture—a transactional promise that lives and dies by presidential mood.

Far from resolving tensions, the arrangement leaves South Korea more exposed. It sends a dangerous signal: tariff relief is not based on law or rules, but on political loyalty.

That turns economic policy into a hostage situation. And for Seoul—especially as it prosecutes former President Yoon Suk Yeol, ideologically a Trump ally—the price of perceived disobedience could be steep.

No Text, No Treaty. The most fundamental issue is that nothing was written down. No memorandum of understanding. No press statement from the U.S. Trade Representative. Not even a tweet. Just a whisper campaign of diplomatic leaks and unnamed sources claiming “a deal” had been struck. In other words: nothing binding, nothing verifiable, and nothing enforceable.

In normal diplomacy, especially on matters as vital as tariffs, paper is everything. Contracts bind. Statements clarify. Legal instruments create accountability. But in this case, South Korea is operating entirely on verbal assurances and informal understandings. That’s not a deal—it’s a gamble.

Trump’s political style thrives on precisely this ambiguity. He avoids formal commitments, preferring the flexibility of gut instinct and leverage-by-uncertainty. For Seoul to treat this as a settled outcome is either naïve or disingenuous.

Divergent interpretations will grow. Within days of the announcement, confusion reigned. South Korean officials suggested the 15% cap covered a wide range of key exports, including automobiles, batteries, and steel. U.S. sources pushed back, calling the number a “guideline” or a “maximum target,” and implying it only applied selectively—and not on steel.

This isn’t miscommunication. It’s standard operating procedure under Trump. Throughout his first term, he encouraged trade partners to believe they had received favorable treatment, only to undermine those claims later — sometimes publicly, sometimes through sudden policy reversals. NAFTA, NATO, the Paris Agreement — all were subjected to this whiplash diplomacy.

The point isn’t clarity. The point is leverage. If the meaning of a deal is in flux, then it can be reinterpreted—or weaponized—whenever politically convenient. South Korea now finds itself locked into a Rorschach test: the deal is whatever Trump says it is that day.

Questionable legality. There’s also the question of whether this kind of arrangement is even lawful. Trump’s tariff powers come primarily from Section 232 (national security) and Section 301 (trade retaliation) of U.S. law. While these grant wide discretion, they require some procedural justification. Pre-committing to limit their use—especially in exchange for foreign investment promises or political cooperation—veers into murky territory.

If South Korean firms are directing new investments toward U.S. swing states in exchange for tariff relief, it begins to resemble transactional favoritism—bordering on an off-the-books quid pro quo. It may not violate any statute directly, but it certainly undermines the integrity of U.S. trade policy.

And unlike past presidents, Trump has no interest in guardrails. Legal frameworks are only as strong as the executive’s willingness to follow them. This deal—if one exists—was made outside the boundaries of transparent negotiation. That alone should disqualify it from being treated as credible.

This is politics, not economics. At its core, the deal’s greatest weakness is not its ambiguity or legality—but its political nature.

Trump does not use tariffs as economic tools. He uses them to punish or reward, based on loyalty. Canada faced tariffs after recognizing Palestine. Brazil was targeted after prosecutors moved against Bolsonaro.

Germany was hit over defense spending. The list goes on.

Tariffs are not about deficits or unfair practices. They are about power. If Trump feels slighted, betrayed, or embarrassed, the tariffs return. If he wants to reward flattery or loyalty, he lifts them. There is no consistency—only impulse.

South Korea is now in a particularly precarious position. The ongoing prosecution of former President Yoon Suk Yeol—who maintains close ideological alignment with Trump—could easily be framed as a hostile act. If the Trump camp interprets Yoon’s legal troubles as political persecution, Seoul may find its “deal” suddenly void. Tariffs could be reimposed not because of any trade infraction, but because Trump feels slighted on behalf of an ally.

This is the price of doing business with a president who runs foreign policy like a patronage network.

The tariff sword still hangs over Seoul. For all the headlines and diplomatic spin, the reality is that South Korea has secured nothing. It has a ghost deal—unwritten, unsettled, and totally dependent on Trump’s volatile temperament. The appearance of relief masks a deeper vulnerability.

In this environment, the sword of Damocles hangs over every U.S. partner. Tariffs can be reimposed with a tweet. Agreements can evaporate overnight. What other issues besides overzealous prosecution of Yoon, could raise Trump’s ire? Here’s a quick list:

• Defense expenditure less than 5% of GDP
• Reluctance to declare a position on Taiwan.
• Building relations with the BRICS.
• Insufficient financial tribute for U.S.F.K in future “separate” negotiations.
• Dithering on U.S.-led efforts to contain China.
• Public criticism of Trump or anything related to Trump.
• Any indication of support for anyone opposed to Trump.

The rules are whatever Trump decides they are. Failure to show visible, personalized obedience—preferably with headlines and ribbon-cuttings—may lead to sudden punishment.

And unlike with institutions, there’s no appeal. Only submission or retaliation. South Korea, exposed by its dependence on U.S. trade and distracted by internal political dramas, is an easy target.

Rather than celebrating this arrangement, Seoul should prepare for its collapse.

The next tariff hike may not come because of trade issues at all—but because of a courtroom decision involving Yoon, a diplomatic vote on Palestine, or a poorly timed statement by a Korean official. This is not stability. It is blackmail.

And in Trump’s world, blackmail is the point.