What if the Taiwan Strait were blockaded?

After US President Donald Trump ordered a blockade on the Strait of Hormuz, some Chinese netizens astutely observed that at least the US and Iran had reached one point of consensus: setting up toll booths in the strait.

Chinese netizens have long been known for their sharp take on current affairs, posting a flurry of jokes and self-mockery about this “double toll” at sea.

“Can’t open it? Just add another lock!”

“Why doesn’t China join in too? Use Gwadar port as a point and charge a fee — let’s all get a piece of the pie.”

“Access on one side means getting blacklisted on the other!”

Some even shared diagrams of the “dual toll booths at sea”, with Iran’s gate drawn at the Persian Gulf end while the US’s booth is marked in the Gulf of Oman, locked in opposition.

Trump’s quirky “Don Tzu’s art of war” has given Chinese netizens plenty to talk about. But if such a toll booth were set up in the Taiwan Strait, would public opinion on the mainland remain relaxed? That seems unlikely.

Every war reshapes how countries think and craft policies, while preparing the ground for the next conflict. The Russia-Ukraine war highlighted the strategic value of drones in modern warfare. The Gaza war marked the arrival of a hybrid era with high-value weapons alongside cheap expendables. What lessons, then, does the blockade and counter-blockade between Iran and the US in the Strait of Hormuz offer the rest of the world?

A natural inference is that if war were to break out in the Taiwan Strait and the mainland were to impose a blockade, the global fallout could be even more devastating than the crisis in the Strait of Hormuz.

An article in The Atlantic titled “What China Just Learned from the Iran War” argued that although Beijing has multiple options for using force against Taiwan, the most attractive is to begin with a partial blockade of the island — a tactic closely resembling Iran’s moves in the Strait of Hormuz.

As for how such a blockade might work, Eyck Freymann, a Hoover fellow at Stanford University, wrote in the Financial Times that Beijing would not need to attack merchant ships — it could simply issue a unilateral legal declaration asserting the right to control which vessels enter and leave Taiwan, or fire missiles and bullets to declare “exclusion zones” in the Taiwan Strait.

He added that even short of outright conflict, if the risk of escalation seems high, private carriers would face pressure to avoid the waters and airspace around Taiwan. If Iran can deter shipping companies from braving the Strait of Hormuz using drones alone, “imagine asking them to take on the People’s Liberation Army”.

The closure of the Strait of Hormuz has disrupted about 20% of global oil supply, triggering sharp volatility in energy and financial markets. If a similar scenario unfolded in the Taiwan Strait, trade, finance and supply chains would all be hit by systemic shocks with far broader repercussions.

The Taiwan Strait is a key route for about one-fifth of global maritime trade. More crucially, Taiwan produces around 90% of the world’s most advanced semiconductor chips which are used in AI systems, electronic products and military technologies.

US consultancy Rhodium Group estimated that a blockade of the Taiwan Strait would cause economic losses of up to US$2 trillion. Meanwhile, Bloomberg Economics estimated that if an actual armed conflict were to break out — such as the US Navy escorting vessels to break the blockade — the losses could hit US$10 trillion, or about 10% of global GDP, plunging the world into an economic depression like the one in the 1930s.

Once the Taiwan Strait is blockaded, it will inevitably escalate into a global economic and geopolitical crisis, and the key variable shaping the regional security landscape will be whether the US intervenes.

A report released by the Washington-based Center for Strategic and International Studies last year stated that in 26 wargames based on a mainland blockade of Taiwan, the US Navy faced catastrophic outcomes each time it attempted to break the blockade. A journalist from The Atlantic relayed the authors’ view that it would constitute a major battle, with the potential loss of hundreds of vessels even in the early stages. The report therefore concludes that any blockade would place the US president in a dilemma.

Judging from Trump’s conduct during the Iran war, there is a clear gap between rhetoric and action: while he threatened to destroy Iran’s entire civilisation, he failed for a long time to prise open the Strait of Hormuz, instead adopting a reverse blockade strategy by cutting off Iran’s routes for exporting crude oil and earning revenue in an attempt to draw China, the primary buyer of Iranian oil, into the fray.

Some argue that any future US president will act like Trump — weighing not only military casualties in decision-making, but also political costs such as the domestic economy’s capacity to absorb shocks and the level of public support. Thus, if the Taiwan Strait were to be blockaded in future, the US’s stance and actions may well fall short of Taiwan’s expectations.

However, it cannot be ruled out that the importance of Taiwan’s semiconductor industry would make it difficult for the US to remain entirely on the sidelines. Rather than intervening directly, it may become involved through an “alliance-based” approach, encouraging allies such as Japan, the Philippines and Australia to respond collectively, while shifting the battleground into the financial and technological domains — for instance, through financial sanctions. In other words, any future crisis in the Taiwan Strait is likely to involve multi-layered competition in the areas of the military, economy and diplomacy.

From the Russia-Ukraine war to the US-Iran conflict, the recurring pattern that wars are easy to start but difficult to end continues to play out. Trump said on 15 April that the Iran conflict was “very close to over”, though how credible this claim is remains to be seen. That same day, he also praised himself on social media, claiming that China was “very happy” with his “permanent opening” of the Strait of Hormuz, and asserting that Beijing had agreed to stop supplying weapons to Iran. He further claimed that when he arrives in China in a few weeks, Chinese President Xi Jinping would give him “a big, fat, hug”.

If the Xi-Trump meeting does indeed take place in May, issues such as the Middle East and the Taiwan Strait will inevitably be unavoidable. Observers are not only watching whether the two leaders exchange a warm embrace, or whether China and the US can reach concrete agreements or even a dramatic “grand bargain”, but more importantly whether, amid a complex interplay of issues, both sides can establish a degree of “stable expectations” for future interactions and create a “safety buffer” for potential flashpoints.

This article was first published in Lianhe Zaobao as “台湾海峡如果被封锁”.

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