What if China quarantines Taiwan by inspecting every inbound ship?
A customs 'quarantine' of Taiwan-bound shipping chokes the world's leading-edge chip supply without a shot fired: TSMC and the semi sleeve gap down, VIX bids, and Nasdaq leads losses as fab single-point-of-failure risk reprices. Closest rhyme is the April 2025 100%+ tariff spiral that knocked semis and spiked gold; here the lever is logistics, not duties. Forward angle: a sub-kinetic blockade is harder for the US to answer militarily, so the equity drawdown could persist longer than a clean tariff headline.
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The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (electric blue) over time vs the market's (Polymarket, amber), from the past toward the 0–6 months horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. Loading the probability audit trail…
What it would mean
If this plays out, it is a risk-off shock. China declares law-enforcement quarantine inspecting all ships bound for Taiwan, stopping short of military blockade but choking trade. The trigger decomposes into signed root‑shocks — Geopolitical risk ▲ · Semiconductor supply risk ▲ · Trade tension ▲ — which propagate through our causal graph to the markets below.