United States and the Taiwan Strait → Taiwan (Republic of China)

The parties

• United States and the Taiwan Strait provides material support to Taiwan (Republic of China)
• Taiwan (Republic of China) receives material support from United States and the Taiwan Strait

A directional arrangement: the two parties do not hold the same position in it. Authored once and read from both ends.

Status

Active

In force and operating. Says nothing about how well it is working, or about which way it is heading.

Last material change: 2026-05.

What the arrangement covers

Categories the arrangement is documented to include. Not a measure: a relationship covering more of them is described in more detail, not held more firmly.

Summary

The United States is Taiwan's principal arms supplier and security reference point, selling under the 1979 Taiwan Relations Act — a domestic American statute rather than a bilateral treaty, which is the structural point. In December 2025 the administration notified Congress of more than eleven billion dollars in new Foreign Military Sales cases, the largest single package by value in the history of the relationship. In mid-May 2026 the President said publicly that he had not approved a further package, reported at around fourteen billion, that the decision depended on China, and that it was a good negotiating chip. The two together are the record: the supply is large, it is governed by American domestic process, and in 2026 it was openly described as an element in a negotiation with the other party.

Why it matters

Taiwan's defence planning assumes a supplier whose decisions are made in another country's political calendar and, in 2026, explicitly with reference to relations with Beijing. That makes the delivery pipeline a political variable rather than a logistical one, and it is why this module treats American arms decisions as an observable in their own right.

Agreements

• Taiwan Relations Act · signed 1979

  A domestic United States statute, not a bilateral agreement and not a defence commitment. It provides the legal basis for arms sales and for unofficial relations, and obliges no particular response to an attack.

Related events

• The largest US arms package ever notified for Taiwan December 2025

  Weapons deliveries · Diplomatic

• A $14bn package is held back as a "negotiating chip" 2026

  Weapons deliveries · Diplomatic

What remains unknown

• Vigil publishes no quantities, delivery schedules, backlogs or inventory figures. Notification, approval, contracting and delivery are four different stages and reporting frequently conflates them; this record does not attempt to reconcile them.
• The status of the reported $14bn package at the time of review is not resolved, and no source establishes what would release it.
• Training and advisory activity is described at the level of published reporting. Its scale, locations and content are not recorded here.

Readings the evidence also supports

• The 2026 handling can be read as a transactional approach that has devalued a deterrent resting on belief, or as a negotiating posture with no effect on what is eventually delivered. The distinction is not resolvable from outside and matters more than the dollar figures.

Listed because the record's own assessment is not the only one its sources permit — not as a hedge on the assessment above.