IRGC forces US troops out of Hormuz Strait after Iranian ship attack

The IRGC forced US troops out of the Strait of Hormuz after attacking an Iranian ship, and the Polymarket contract on UK warship transit through the strait by April 30 has dropped to 8.5%, down from 12% a day ago.

The market for ship transits through the Strait of Hormuz between April 8-12 reflects the IRGC’s tightening control over the waterway. Traders are pricing in reduced likelihood of ten ships transiting on any given day during this window. The April 30 UK warship transit contract’s 3.5-point drop in a single day tracks directly with the IRGC’s actions in the strait.

Volume on the warship market is thin: $5,648 in USDC traded over 24 hours. It takes just $304 to move the odds five points, meaning a single order can produce visible swings. The largest move was a 2-point spike at 4:25 PM, likely from one trade. This is a market where individual orders move prices, and sentiment around naval operations in the strait is reactive to each new development.

The IRGC’s move comes during ongoing ceasefire talks, and it could undermine those negotiations or escalate military confrontations. At 8.5¢, a YES share on UK warship transit pays $1 if it resolves, a 11.8x return. For that bet to pay off, the UK would need to defy current tensions and send warships through the strait within 12 days.

Watch for CENTCOM activity and any statements from the UK Ministry of Defence on naval deployments. Changes in military posture or diplomatic moves could shift these odds quickly given how little volume it takes to move the market.

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