US Stock Market Today | Dow Jones | Nasdaq Live: US futures decline as Iran tensions keep investors cautious; earnings mixed

Will President Donald Trump send troops into Iran? Will he rename the Strait of Hormuz after himself? Will he post again praising Allah? No one knows the answers, but online betting companies that allow people to wager on Trump policies and statements are profiting — including some backed by his oldest son.

Prediction markets love the president’s unpredictability, his need to keep people guessing about his next move or social media post, leading to more wagers in these betting venues and more fees for them. That includes Polymarket, a company Donald Trump Jr. has a stake in, and Kalshi, a company he advises.

These sites have to come up with new betting lines on current events everyday, and Trump Jr.’s famously fickle father has proven to be a rich source of will-he-or-won’t-he questions.

When a wagering event on Polymarket asked whether Trump was likely to send troops into Iran, nearly 100,000 bets were placed on April 8, leading to the biggest trading day of the year up to then.

And Trump’s policies and social media comments generate bets beyond the war-related ones: Who will Trump back to run Venezuela? Will his insults of Pope Leo XIV continue? Will he seize Greenland?