Specifically: https://en.wikipedia.org/wiki/Presidential_Emergency_Operations_Center https://en.wikipedia.org/wiki/Presidential_Emergency_Operati... During 911

Specifically: https://en.wikipedia.org/wiki/Presidential_Emergency_Operations_Center https://en.wikipedia.org/wiki/Presidential_Emergency_Operati... During 911, the President who was not in Washington at the time was flown to a nuclear bunker: https://www.wowt.com/2021/09/08/20-years-after-911-look-inside-stratcom-bunker/ https://www.wowt.com/2021/09/08/20-years-after-911-look-insi...