Summary: Last month, during the longest government shutdown in U.S. history, Treasury Secretary Scott Bessent announced that the United States had offered to functionally loan Argentina $20 billion. Despite the sums involved, this bailout required no authorization from Congress, because of the loan’s source: an obscure pool of money called the Exchange Stabilization Fund. The ESF is essentially the Treasury Department’s private slush fund. Its history goes all the way back to the Great Depression. But, in the 90 years since its creation, it has only been used one time at this scale to bailout an emerging economy: Mexico, in 1995. That case study contains some helpful lessons that can be used to make sense of Bessent’s recent move. Will this new credit line to Argentina work out as well as it did the last time we tried it? Or will Argentina’s economic troubles hamstring the Exchange Stabilization Fund forever?Pre-order the Planet Money book and get a free gift. /  Subscribe to Planet Money+Listen free: Apple Podcasts, Spotify, the NPR app or anywhere you get podcasts.Facebook / Instagram / TikTok / Our weekly Newsletter.This episode was hosted by Keith Romer and Erika Beras. It was produced by Luis Gallo. It was edited by Eric Mennel and fact checked by Sierra Juarez. It was engineered by Cena Loffredo. Alex Goldmark is Planet Money’s executive producer.