The new Trump Accounts are designed to give millions of American children a head start in the stock market. Besides the kids who are eligible for $1,000 in free money, there's another surprise winner: the State Street SPDR Portfolio S&P 500 ETF (SPYM). Thanks to its rock-bottom 0.02% fee, the fund has become the default investment for the new accounts — a designation that could funnel tens of billions of dollars its way and even reshape the competitive landscape for S&P 500 funds.

On this episode of Trillions, Eric Balchunas and Joel Weber explain why SPYM is the ETF of the Moment. They unpack how Trump Accounts work and how they could reshape stock ownership in the US. Then they explore SPYM's surprising backstory, its rivalry with its older sibling, State Street's legendary SPY, and why the policy could, in Balchunas's view, ultimately make the US stock market "too big to fail."

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