COMMENTARY: Trump governs by Truth Social posts — and it works, which is terrifying

Introduction: An ordinary Friday, a 100% tariff threat

The post that shook global markets

On Friday, June 26, 2026, in the late afternoon, United States President Donald Trump published a message on his Truth Social platform threatening to impose 100% tariffs on exports from any country that levied a Digital Services Tax (DST) on American technology companies. The message was direct, unequivocal, and of potentially colossal economic reach. It explicitly named "many European countries" in the process of discussing the imminent implementation of such a tax.

Trump added that this 100% tariff would "supersede any trade deal with the country, whether implemented, signed, or not." This post was published one day after the European Union had given its final approval to a trade deal with Washington that had taken months to negotiate. Translation: in a single social media message on a platform he created for himself, Trump potentially invalidated a major multilateral agreement, triggered a panic reaction across European chancelleries, and may have launched a new phase of the transatlantic commercial war.

This isn't new — it has become the norm

This is not the first time Trump has governed by Truth Social post. His second-term administration has systematised this practice: tariff announcements, diplomatic ultimatums, threats of commercial retaliation — everything flows through a social media platform he controls entirely, bypassing the usual institutional processes of verification, consultation, or coordination. As early as 2025, he had forced Canada to back down on its digital tax with a similar threat posted on Truth Social.

The mechanics of governing by post

How a single message disrupts markets and diplomacy

Analysing a Trump Truth Social post as a mere communications message is to miss the point entirely. These posts function as real and immediate foreign policy instruments, with measurable effects on financial markets, diplomatic decisions, and state behaviour. The post of June 26 immediately triggered reactions across several European capitals. France, whose president Emmanuel Macron had declared his intention to maintain the French digital tax on American companies, found itself in the front line. The United Kingdom also had to defend its position.

This ability to generate instant political urgency is one of the central strengths of the Trump method. Before institutional deliberations can begin, before diplomatic cabinets have had time to formulate a coordinated response, the market and the media have already absorbed the threat as real. Bloomberg, Wall Street Journal, CNBC, Al Jazeera, Politico — all treated this post as a major foreign policy decision, which gives it effective reality even without a formal presidential decree.

Legal authority: an open question

The United States Supreme Court declared unconstitutional the sweeping tariffs imposed by the Trump administration under the International Emergency Economic Powers Act (IEEPA). Trump responded by seeking alternative legal bases — notably Section 122 of the Trade Act of 1974 — to maintain a global 10% tax on imports. The question of what law would allow him to instantly impose 100% tariffs on specific countries simply because he wrote it on Truth Social remains legally very unclear, according to CNBC.

The immediate context: the EU-US deal threatened the day after its signing

A deal ratified yesterday, threatened today

On June 25, 2026, European Union Council members gave their final approval to the EU-US trade agreement, establishing a cap of 15% on most European tariffs toward the United States in exchange for the removal of European tariffs on American industrial goods. This agreement had taken nearly a year of difficult negotiations, with safeguard clauses allowing the EU to suspend tariff preferences if Washington failed to honour its commitments.

Less than 24 hours after this ratification, Trump published his Truth Social post threatening 100% tariffs that "supersede" any trade deal. This timeline is revealing: either Trump did not know the agreement had just been ratified (unlikely), or he did not care, or he was deliberately seeking to maintain maximum pressure on his trade partners even after a deal had been signed. According to Politico, this threat "risks complicating trade negotiations with the European Union."

France in the crosshairs: wine versus digital

France has long been in Trump's sights on the digital tax question. In June 2026, during the G7 hosted by France, Trump had already threatened 100% tariffs on French wines and champagne if Paris did not exempt American companies from its 3% digital services tax. This specific threat illustrates how Trump uses Truth Social: declarations are precise enough to signal intent, vague enough to preserve flexibility. "I told them not to tax American companies, and if they do, I have no choice" — this is diplomatic blackmail, clearly articulated.

The impact on allies: between irritation and adaptation

European diplomats in permanent crisis-management mode

European capitals have since 2025 developed an informal protocol for monitoring Truth Social: diplomatic teams monitor Trump's account in real time and are ready to activate crisis cells if a major post appears. This adaptation reveals how thoroughly governing by post has changed diplomatic practices. American embassies in European capitals are playing an increasingly diminished role — it is Truth Social, not the State Department, that now articulates American commercial policy first.

This situation is particularly problematic for partners who signed deals with Washington believing they had secured a degree of stability. When the American president can invalidate a trade deal with a post on a social media platform he owns, the value of those deals becomes fundamentally uncertain. For European companies that had already adjusted their export strategies based on the EU-US agreement ratified on June 25, this post of June 26 is a real and immediate source of risk.

Trump: the necessary evil for the Western economic order?

Intellectual honesty requires acknowledging: European digital taxes primarily targeting Google, Apple, Meta, Amazon, and Microsoft raise legitimate questions of commercial reciprocity. These companies generate enormous profits in Europe, fiscally optimise their presence, and European states legitimately seek to capture part of this economic value. The fundamental tension between American technological dominance and Europe's desire for fiscal sovereignty is real.

The doctrine of unpredictability as a pressure tool

The art of the vague but credible threat

Trump's method rests on a well-known doctrine from his first term: strategic unpredictability. By threatening 100% tariffs without a clear legal basis, by linking his threat to any discussion of a digital tax (even in countries that have not yet adopted one), by specifying that his tariff would "take effect immediately," Trump creates maximum uncertainty at minimal political cost. It costs him nothing to publish this post — but the potential consequences for targeted countries are massive.

This asymmetry is the essence of the Trump method. A leader who does not have to consult the Senate, evaluate constitutional implications, or coordinate with allies before making a major statement has a definite tactical advantage over more deliberative democratic systems. The problem is that this speed of decision undermines the durable commitments on which international cooperation rests.

The Canadian precedent as proof of effectiveness

In 2025, Canada abandoned its digital tax on American companies after similar threats from Trump posted on Truth Social. This precedent validates the method — it works. And if it works, Trump will keep using it. The question is no longer whether this form of governance is theoretically good or bad — it is a reality that America's allies must live with.

The history of Trump trade conflicts: threat, negotiation, repeat

The well-tested mechanics of Trumpian commercial pressure

To understand the Truth Social post of June 26, 2026 on digital taxes, it must be placed in the broader context of Trump's commercial strategy. Since his first term, the pattern has been identical: announcement of a spectacular punitive measure — 100% tariffs, sanctions threats, withdrawal from agreements — followed by a period of intense negotiation, then either a concession from the other side (which allows Trump to declare victory), or partial implementation. This mechanism worked with China in 2018–2019 (Phase 1 agreement), with Canada and Mexico to renegotiate NAFTA into CUSMA, and with the European Union on multiple occasions.

This model creates permanent uncertainty for Washington's trade partners, but it also has an internal logic. Trump uses the threat of maximum tariffs as a negotiating tool, knowing that targeted countries often prefer to concede on a specific point rather than risk massive economic retaliation. The problem is that this strategy erodes institutional trust in American trade deals — if a strong enough threat can always modify agreed terms, American commitments lose their predictable value.

The technological context: why American giants are being targeted

Google, Apple, Meta, Amazon — the European fiscal challenge

To understand Trump's fury against European digital taxes, one must understand what they represent in economic reality. American technology giants — Google, Apple, Meta, Amazon, Microsoft — generate billions in revenues in Europe while fiscally optimising their presence to minimise tax in high-rate jurisdictions like France, Germany, or Italy. The Digital Services Taxes (DST) that several European countries have introduced or are considering are an attempt to capture a fraction of this economic value.

From the European perspective, this is a matter of fiscal sovereignty and economic reciprocity: if American companies do business in Europe and extract value from it, they should contribute to European public finances. From the American perspective — and from Trump's — it is discrimination against American companies with no basis in WTO rules. Both perspectives are understandable and the tension between them is real. What is less defensible is the method chosen to resolve it.

The international reaction: between outrage and resignation

Diplomatic responses that reflect dependence

Faced with the 100% tariff threats posted by Trump on Truth Social, international reactions reveal the geography of dependence. The United Kingdom, which maintains its own digital tax, defended its position on June 26 — but without escalation, recalling its attachment to the special relationship with Washington. France, which has maintained its DST despite repeated Trump pressure, finds itself on the front line. The European Union, which has just ratified a trade agreement with the United States, is placed before a dilemma: apply a legitimate digital tax at the risk of triggering 100% tariffs that would wipe out the benefits of the deal it just signed.

This situation — in which a trade agreement can be invalidated by a Truth Social post the day after ratification — illustrates the predictability deficit that characterises current American commercial policy. Multinational companies must manage tariff risks that can appear or disappear with the American president's morning messages. This instability carries a real economic cost, measurable in investment decisions, supply chain strategies, and market expectations.

Conclusion: The West must learn to live with Trumpian unpredictability

Adapting without capitulating

European allies must find a difficult balance: not yielding to unconstitutional or illegal threats from Trump, while maintaining indispensable commercial and security relationships. This position requires more robust European coordination, a rapid-response capability to Truth Social announcements, and above all a clear doctrine on what is negotiable and what is not. The digital tax can be a subject for discussion — but not under the pressure of a Friday afternoon post.

What this method reveals about the state of American democracy

Beyond trade, what stands out about the June 26 post is what it reveals about the state of American institutions: an economic foreign policy that can be modified in 280 characters, without consultation with Congress, without coordination with allies, without assessment of the impacts. This is a presidentialisation of foreign policy pushed to its extreme, and it constitutes a systemic fragility for the credibility of long-term American commitments.

Signed Maxime Marquette, columnist

Columnist's transparency box

My declared biases

I am pro-West and believe the transatlantic alliance is fundamental to European security. I am neither pro-Trump nor anti-Trump — I analyse him as a leader whose methods are effective short-term and potentially disastrous long-term for institutions. My sources include CNBC, Bloomberg, Al Jazeera, Wall Street Journal, Politico, AP.

What I don't know

I do not know whether Trump will actually follow through on his 100% tariff threats or whether this post was a provisional pressure tactic. The precise legal consequences of this post remain uncertain — American courts have already halted some Trump tariffs and could do so again.

Sources

Primary sources

CNBC — Trump threatens 100% tariff on countries putting Digital Services Tax on American Companies — June 26, 2026

Bloomberg — Trump Vows 100% Tariff on Countries Over Digital Services Taxes — June 26, 2026

Al Jazeera — Trump threatens tariffs for countries that levy digital tax on US firms — June 26, 2026

Wall Street Journal — Trump Threatens 100% Tariff on European Countries That Impose Digital Services Tax — June 26, 2026

Secondary sources

Politico — Trump threatens additional tariffs on European countries — June 26, 2026

EFE — EU approves final trade pact with US — June 25, 2026

Grant Thornton — EU-U.S. trade shifts, Trump on USMCA, French digital tax — June 23, 2026