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By Bonnie Yushih Liao 廖雨詩
Reports that the US is preparing a sustained maritime pressure campaign against Iran — including measures amounting to long-term restriction of port access — have shifted debate beyond selective interdictions. As Washington moves toward quasi-blockade dynamics, a familiar question has re-emerged: Could China adopt similar tactics in the Taiwan Strait?
The comparison is misleading. It assumes similar operational behavior produces comparable strategic effects. In practice, the two cases differ at a systemic level.
US maritime operations against Iran function as bounded exceptions within the international order. They are directed at specific targets, justified through legal or quasi-legal frameworks such as sanctions enforcement and counter-proliferation, and calibrated to limit spillover. Even when contested, they do not fundamentally alter global maritime commerce.
A Chinese interdiction of commercial shipping to Taiwan would be seen differently. It would not be seen as selective enforcement, but as interference with routine lawful transit. It would also raise questions about the continued applicability of freedom of navigation in a critical waterway.
The issue is not whether China would face higher legal or political costs, but whether Beijing can conduct limited coercive actions without triggering systemic responses. Evidence suggests it cannot.
In the US case, escalation is constrained by defined targets, flexible legal framing and manageable second-order effects. In the Taiwan Strait, even a single interdiction could activate global risk mechanisms beyond state control.
Shipping insurance markets illustrate this dynamic. The Joint War Committee designates high-risk maritime zones. Reclassification of the Taiwan Strait would immediately raise premiums, redirect shipping routes and disrupt supply chains.
The effects are driven by perceived risk rather than sustained conflict.
Oil price spikes following reports of an extended US blockade strategy show how quickly markets respond. This creates a non-linear environment in which limited actions produce disproportionate effects.
Escalation dynamics reinforce this asymmetry. US-Iran interactions remain regionally bounded, with limited spillover into the global commons.
However, the Taiwan Strait sits within dense economic and security networks, including Japanese energy imports, South Korean trade flows and Taiwan’s semiconductor supply chains.
Even limited disruption would likely prompt external involvement, including naval deployments and escort operations.
The boundary between gray-zone coercion and conventional conflict would narrow rapidly.
This reflects a broader structural difference. The US operates within and sustains the existing system. China is viewed as testing its limits, probing blockade effects short of formal declaration and assessing how far disruption can be normalized without coordinated response, implying reduced controllability.
China might possess the operational capacity to initiate maritime interdictions. What remains uncertain is its ability to manage resulting chain reactions across markets, alliances and security domains. For Taiwan, this distinction is critical. Gray-zone maritime pressure should not be treated as isolated incidents but as part of a cumulative strategy to reshape operational norms.
External actors risk misreading intent if they treat such actions as discrete events. In the maritime domain, normalization is itself escalation — and accepting it might accelerate instability.
Bonnie Yushih Liao is an assistant professor in Tamkang University’s Department of Diplomacy and International Relations.











