There are "continuity of operations" procedures to prevent a "decapitation" strike killing the President & VP, thus preventing the US from retaliating [0]. This

There are "continuity of operations" procedures to prevent a "decapitation" strike killing the President & VP, thus preventing the US from retaliating [0]. This was a plot point in Tom Clancy's novel Debt of Honor [1] (which I distinctly remember reading right before 911, as I had to commute via public transit and commutes were so long I read books). 0 - https://en.wikipedia.org/wiki/Designated_survivor https://en.wikipedia.org/wiki/Designated_survivor Since this person will be offsite in a secure facility/bunker, they'll have the backup nuclear football with them. 1 - https://en.wikipedia.org/wiki/Debt_of_Honor https://en.wikipedia.org/wiki/Debt_of_Honor Which is how Jack Ryan gets "promoted" to President.