Bab el-Mandeb Strait effectively closed by 2026?

Platform comparison

Market context

The Bab el-Mandeb Strait remains a critical chokepoint for global shipping, with over 20,000 vessels passing annually, yet current on-chain pricing on Polymarket reflects a 0% probability that transit calls will drop to ten or fewer by mid-2026. Traders holding USDC on the Polygon network see this contract priced as a near-certainty for “No”, driven by conditional tokens that penalise bets on extreme disruption unless data from IMF PortWatch confirms a collapse in arrivals.

Historically, traffic through the strait has never approached closure; even during heightened tensions between the US and Iran in early 2026, the 7-day moving average of ship calls remained at 33 on 8 March, while January 2026 transits were still up 11% compared to the prior year[1][2]. Past disruptions, such as those linked to attacks in the Red Sea, reduced traffic to below half capacity but never below ten daily calls, framing the current 0% probability as grounded in robust historical resilience rather than abstract speculation[4].

Traders should monitor upcoming announcements on US-Iran security talks and seasonal shipping schedules, as renewed tensions could trigger sharp declines in transit volume. Lloyd’s List Intelligence reports that traffic fell sharply last month due to seasonal slowdowns and security risks, though volumes remain elevated overall[2]. Any sudden drop in the 7-day average below ten would require IMF PortWatch to publish data confirming such a threshold, a dependency that currently appears unlikely given the settlement window ending 2026-06-30.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.