Amid reports that over 5,000 U.S. Marines—alongside multiple Amphibious Ready Groups (ARGs)—and several thousand troops from the 82nd Airborne Division are deploying to the Middle East, market sentiment on Polymarket has shifted sharply.

The perceived likelihood of a U.S. ground invasion of Iran before the end of 2026 has risen to around 57%, an increase of more than 40 percentage points since early March.