Why does the U.S. government lock medicine away in secret warehouses?

https://www.npr.org/2022/12/23/ [login to see] /strategic-national-stockpile-medical-warehouses
Surges in COVID-19, the flu and other respiratory illnesses are forcing the U.S. government to do something it normally reserves for emergencies: release hoards of stockpiled Tamiflu to states in dire need of more flu medicine.

The move from the Department of Health and Human Services on Wednesday came via the Strategic National Stockpile (SNS), which allows the government to tap its reserves of medicine and other medical supplies when a mass outbreak or other health crisis occurs.

It's true. There is a network of warehouses, each the size of several Walmart Supercenters, located in top-secret locations across the country. And while much about the stockpile remains a secret, it continues to play a vital role in the COVID pandemic.

Here's what we know about the multibillion-dollar inventory of vaccines, equipment and other medical supplies designed to help save lives.