Strait Layers | Interactive Deterrence

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Route profile

PLA aircraft around Taiwan, daily · TSM PLA Activity Center

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How to read the map

Anti-access/area denial is layered. The outer layers, long-range ballistic missiles like the DF-26 and DF-21D, are meant to keep U.S. forces far from Taiwan. The inner layers, coastal cruise missiles and long-range surface-to-air missiles, are meant to make the Strait itself too dangerous to operate in. The further out a layer reaches, the more it depends on someone else to tell it where to aim.

Abbreviations: IRBM, SRBM = intermediate- and short-range ballistic missile; ASBM = anti-ship ballistic missile; SAM = surface-to-air missile; OTH radar = over-the-horizon radar; ADIZ = Taiwan's air defense identification zone; PLAN = PLA Navy; CCG = China Coast Guard.

That is why a range ring overstates the threat. A missile that can fly 1,500 km only threatens a ship at 1,500 km if the PLA can find the ship, fix its position, keep the track current and push a firing decision through command channels in time. U.S. doctrine calls this sequence F2T2EA.

FindSomething detects a ship out there.

FixIts position is known well enough to aim at.

TrackThe position stays current as the ship moves.

TargetA shooter is assigned and cleared to fire.

EngageA weapon in range launches.

AssessSomeone checks whether it worked.

The same logic runs the other way. A PLA amphibious force crossing the Strait sails into Taiwan's own coastal missiles, drones and mines, and the PLA's first task is to blind and suppress them. The PLA crossing tab shows that contest; Salvo math shows what happens once missiles are in the air; TSM activity grounds all of it in the daily record.

Sources and method

Weapon ranges: CSIS Missile Defense Project, Missile Threat: China. DF-26 4,000 km; DF-21D about 1,450–1,550 km per U.S. reports; DF-15 variants 600–900 km and DF-16 800–1,000 km (the SRBM ring is drawn at 900 km); YJ-18 220–540 km; ATACMS 300 km (Block 1A). The U.S. Department of Defense gives DF-15 725–850 km, DF-16 more than 700 km, DF-21D more than 1,500 km and DF-26 3,000–4,000 km (2024 China military power report, p. 64).

Coastal cruise missile, SAM, Taiwanese weapon (except ATACMS) and all sensor ranges are notional round numbers (marked *), chosen to show how the layers relate rather than to describe specific units. Ring centers are representative launch areas, not identified sites.

Activity data: Taiwan Security Monitor PLA Activity Center, China Coast Guard Incident Tracker and Taiwan Strait Transit Tracker, compiled from Taiwan Ministry of National Defense and Coast Guard Administration releases. Taiwan ADIZ boundary: TSM GIS layer.

Scenario framing: Cancian, Cancian and Heginbotham, The First Battle of the Next War, CSIS, January 2023. Sensor types: U.S. Department of Defense, Military and Security Developments Involving the People's Republic of China: the 2020 report describes sky wave and surface wave over-the-horizon radars working with reconnaissance satellites to target long-range strikes, and the 2024 report covers the KJ-500, ISR satellites and HQ-9 and S-400 air defenses. Kill-chain steps: Air Force Doctrine Publication 3-60, Targeting (F2T2EA).

The models are deliberately simple. Every sensor is on or off; weather, deception, reloads, timing and damage are left out. Use them to reason about structure, not to predict outcomes.

How to read the map

Bases under the umbrella

Sources and method