臺灣海峽基準 — 2026年7月20日

Taiwan's Ministry of National Defense has continued publishing daily summaries of detected PLA aircraft and vessels throughout 2026, and the monthly totals have run closer to pre-2024 levels than to the elevated tempo that followed President Lai's May 2024 inauguration, when detected activity roughly doubled to over 300 sorties per month at peak. Daily figures in mid-July 2026 were in the low single digits of aircraft sorties alongside several naval and official vessels, with median-line crossings still routine. Analysts read the change as an adjustment in coercion strategy rather than a reduction in objectives.

Why it matters. This is the module's most consequential current fact and its easiest to misread. A lower sortie count is not de-escalation if pressure has shifted into instruments nobody counts — coast guard presence, economic measures, information operations. The median line remains crossed routinely, which means the 2022 ratchet has not been given back; only the tempo above it has changed.

• China & Taiwan Update, July 17, 2026 — American Enterprise Institute, 2026-07-17
• PLA activities in the waters and airspace around Taiwan — Ministry of National Defense, ROC (Taiwan), 2026-07-14
• China's Taiwan Drills Are Crossing a New Line — The Diplomat, 2026-01-15

China Coast Guard patrols in waters around Kinmen, recurring since February 2024, have continued through 2026, with reporting indicating a more regular CCG presence east of Taiwan as well. Taiwan's Coast Guard Administration briefed visiting international lawmakers on the pattern in July 2026. Separately, reporting suggested Chinese messaging that could support contesting Philippine sovereignty over the Batanes islands in the Luzon Strait.

Why it matters. Coast guard activity is the purest grey-zone instrument in this system: presence framed as law enforcement makes a military response disproportionate and a non-response a tacit concession. Extension to the east of Taiwan would matter more than the sortie numbers, because it describes pressure applied all the way around the island rather than across the strait.

• China & Taiwan Update, July 17, 2026 — American Enterprise Institute, 2026-07-17
• China & Taiwan Update, July 2, 2026 — American Enterprise Institute, 2026-07-02

In May 2026 Taiwan's Legislative Yuan passed a multi-year special defence budget of NT$780bn (around $24.8bn), after months of gridlock. The figure is roughly 38% below the NT$1.25tn the Lai administration sought to fund US procurement, domestic industry and the integrated air-defence programme publicised as "T-Dome" — and substantially above the NT$380bn the Kuomintang initially proposed. The administration's stated targets remain above 3.3% of GDP for 2026, rising toward 5% by 2030.

Why it matters. This is what deterrence looks like when it runs through a democracy with a divided government: contested, reduced and slow. Reading the outcome as Taiwanese indifference would be wrong — the final figure doubled the opposition's opening position — but so would treating stated targets as delivered capability. From here the informative indicator is execution: what is actually contracted and spent.

• Taiwan Passes Special Defense Budget to Better Deter China — Bloomberg, 2026-05-08
• Defense in a democracy: Political competition and Taiwan's special defense budget — Brookings Institution, 2026-06-01
• The Contents and Controversies of Taiwan's Special Defense Budget — Global Taiwan Institute, 2026-03-01

Reporting through the first half of 2026 described a slowdown in US arms transfers to Taiwan, including a package reported at around $14bn that remained unsigned, with President Trump publicly describing it as a negotiating element in dealings with Xi Jinping. A February 2026 executive order set out an "America First Arms Transfer Strategy" prioritising recipients that spend more on their own defence and occupy critical strategic geography.

Why it matters. Deterrence is a belief held by the other side, and credibility is its cheapest and most reversible component. Publicly linking Taiwan arms transfers to a broader negotiation is therefore consequential independently of what is ultimately delivered. This is the variable that moved furthest in 2026 — not Chinese capability, but confidence in the guarantee that offsets it.

• U.S. Halts Taiwan Arms Package as Trump Courts China — Foreign Policy, 2026-05-26
• Will Trump Continue to Slow Arms Sales to Taiwan? — Global Taiwan Institute, 2026-04-01
• How do US arms sales to Taiwan work and why are they such a sore point in relations with China? — CNN, 2026-05-29

TSMC reported in July 2026 that it is accelerating construction at its Arizona site against AI-driven demand, having committed substantial additional capital across 2025–26, with advanced-node equipment installation running ahead of schedule and production targeted for 2027. Its most advanced processes remain concentrated in Taiwan. Chinese customers account for roughly 8% of revenue, and its older-node China operations continue under an export licence renewed at the start of 2026. A January 2026 US rule change moved certain advanced AI accelerators from a presumption of denial to case-by-case review.

Why it matters. Overseas capacity reduces global exposure at the margin and over years, not in character — the supplier, materials and packaging ecosystem around Hsinchu is far harder to relocate than the fabs. The strategic tension is real and unresolved: onshoring lowers the world's exposure to disruption, which is desirable economically and arguably weakens the deterrent value of concentration.

• TSMC is accelerating Arizona factory buildout to capitalize on AI 'megatrend,' CFO says — CNBC, 2026-07-20
• TSMC brings its most advanced chipmaking node to the US yet — Tom's Hardware, 2026-04-15

Chinese economic and informational pressure on Japan, applied since November 2025 in response to Prime Minister Takaichi's remarks that an armed attack or blockade of Taiwan could permit a Japanese response, has continued into 2026. In July 2026 Japan announced development of its first centralised national intelligence body since the Second World War, consulting partners including the United States, Germany and Australia on cyber defence and investment screening.

Why it matters. Two things are being tested at once. Japan's statements were the most explicit modern linkage of Taiwan to Japanese defence; Beijing's response demonstrated that positions on Taiwan now carry direct costs for third countries. Whether that deters regional alignment or accelerates it is genuinely open, and current evidence points both ways.

• China & Taiwan Update, July 17, 2026 — American Enterprise Institute, 2026-07-17
• Rising sun: Japan signals stronger support for Taiwan's security — Washington Times, 2026-06-11

Taiwan's Legislative Yuan passed amendments on 13 July 2026 enabling satellite communications providers to operate more readily, addressing exposure to disruption of undersea cables. This follows the 2023 severing of both cables serving the Matsu islands and further incidents during 2025, and sits alongside a reported NT$564.5bn ten-year grid hardening and decentralisation programme and an international cable-resilience initiative.

Why it matters. Resilience is the most trackable part of deterrence: programmes are announced, funded and either delivered or not, whereas intentions are hidden and military balance is contested. It is also the area where Taiwan can act without any foreign approval — which, in a year defined by uncertainty about external support, is a larger point than it first appears.

• China & Taiwan Update, July 17, 2026 — American Enterprise Institute, 2026-07-17
• Taiwan's Push for Societal Resilience — German Marshall Fund, 2026-02-01