Conflict-Driven Chokepoint Disruptions | Council on Foreign Relations

Much of the global flow of goods runs through a small number of maritime straits and international canals. The same market efficiency that creates those concentrations means the supply chains routed through them commonly lack alternatives to mitigate the impact of disruption. It will only become easier to interfere with or even close off chokepoints as cheap drones, unmanned surface vessels, and anti-ship missiles proliferate among state and nonstate actors alike. In such crises, beyond immediate decisions to secure the safety of U.S. citizens, vessels, and military assets, policymakers need to consider what interests are at stake and orient the U.S. response accordingly. Based on lessons from the United States' and other countries' responses to chokepoint crises over recent decades, four lessons stand out:

This playbook outlines four different strategies the U.S. government can adopt toward such crises:

1.0 Situational Assessment

This playbook addresses the disruption of globally critical supply chains through geographic chokepoints by a belligerent actor—state, proxy, or armed nonstate group—physically threatening or closing a maritime strait or canal that conducts a disproportionate share of global trade. Attacks on overland routes, though temporarily costly, are far easier to adapt to and have not historically threatened U.S. interests to the same extent.

Global value chains are organized as hub-and-spoke networks in which flows of goods (spokes) concentrate at a small number of geographic nodes (hubs). A credible threat to a single hub can cascade through the entire network with costs that vastly exceed the directly affected supply chain. These chokepoints are economically efficient but typically lack resilience against conflict or coercion.

The chokepoints in question cover maritime straits, such as Hormuz, the Bab al-Mandeb, Malacca, and Taiwan; and international canals and their approach corridors, such as Suez, Panama, and the Turkish Straits (Bosphorus). They also cover critical infrastructure nodes—the hubs—where disruption affects production, processing, and distribution facilities. Examples of infrastructure nodes include Ras Laffan Industrial City in Qatar, which produces 20–22 percent of global liquefied natural gas (LNG) supply and approximately 20 percent of global helium; Kharg Island in Iran, which houses approximately 90 percent of Iranian crude export capacity; and the Abqaiq-Khurais complex in Saudi Arabia, which processes approximately 7 percent of global crude production. Threats to straits and canals demand drastically different responses than threats to production and processing hubs. Transit disruptions can be resolved by restoring physical access—through military pressure, diplomatic negotiation, or convoy escort. Production and processing disruptions, however, involve destruction or impairment that cannot simply be reopened: they must be rebuilt. The Houthi/Iranian 2019 Abqaiq-Khurais strikes removed approximately 5.7 million barrels per day (bpd) overnight; recovery depended entirely on Saudi Aramco's pre-built redundancy, not on any U.S. response. Without equivalent redundancy—as at Ras Laffan—disruption causes sustained supply reductions that no standard crisis tool can correct.

There are four categories of possible threats, each of which demands different responses from U.S. policymakers:

Across different cases, the consistent failure afflicting policymakers is not a lack of intelligence; it is a lack of preparation. Credible commercial and intelligence analysis warned of Iran's likely closure of the Strait of Hormuz weeks before disruption. The same pattern appeared in 2023: Houthi anti-ship capabilities were assessed before October 7, but no commercial shipping contingency was in place when attacks began in November. Prior to Russia's 2022 invasion, analysts assessed Russian capacity to disrupt Ukrainian Black Sea grain exports; no mechanism to release stockpiled food equivalent to the International Energy Agency (IEA) oil reserve existed. The following information will be essential for pre-crisis contingency planning:

Crisis assessment compresses the pre-crisis framework: actions that normally take days have to be initiated within hours. There are additional crisis-specific information requirements:

2.0 Assessment of U.S. Interests