Prediction markets, which essentially allow users to gamble on almost anything, are on the rise. But what are the ethics of companies that allow people to bet on the possibility of nuclear war?

In the latest episode of Last Week Tonight John Oliver unpacks that exact question, while also digging into other issues — like the possibility of insider trading — faced by leading platforms Kalshi and Polymarket.

"It sure seems like right now we've effectively got gambling sites operating even in states where gambling is illegal, and offering bets on things that there have been laws against for over a decade now," Oliver says in the clip above. "There are a bunch of cases making their way through the courts right now, but it's not clear how they'll resolve, and it's probably going to be in front of the Supreme Court. Meanwhile, Congress is considering a number of proposals tackling aspects of this issue, although given that the President of the United States has a kid currently advising both major companies, I wouldn't hold your breath."

Meaningful policy change in the near future, Oliver says, seems unlikely.

"But at some point we do need to put in place some basic guardrails here. And until then, if we can't change how these sites operate, we should at least try and change how we individually see them. One thing that would frankly help is if news organisations stopped laundering these companies' reputations for them by putting their odds on screen like they are actual news," the host continues.

"Look, on a personal level, if you're considering using these markets to gamble, try and remember that you are statistically likely to lose money. And while I am not against gambling per se, there is something so grim about these sites turning every aspect of our lives into a bet. Because sure, money can be won on them. But in that happening, something also gets lost. Specifically a society where things aren't only weighed in financial terms and where people engage with news for what it means to human beings, not just because they have $50 riding on it. And when something unexpected happens in the world, it would be really nice not to have to automatically question whether it's only because someone is trying to move a market."

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