For a two-hour period on Tuesday night, one current Cabinet member was missing and in hiding, in case of an unthinkable attack on Washington.
The tradition of the “designated survivor” goes back to the 1950s, when the United States and the Soviet Union locked horns in a nuclear stalemate. The process was so secret that it wasn’t really acknowledged publicly by the government until the 1980s.
One Cabinet member is picked by the president to get a special invitation to not attend the State of the Union speech.
For Tuesday's State of the Union, the designated survivor was Energy Secretary Steven Chu.
Last month's presidential inauguration also had a designated survivor, Veterans Affairs Secretary Eric K. Shinseki.
State of the Union attendees include the president, vice president, Cabinet, Congress, and Supreme Court, so any terrorist attack or similar event could wipe out the entire line of succession.
The presidential line of succession is covered in both Article II, Section 1 of the Constitution, which was later amended and clarified by the 20th Amendment, and detailed in the Presidential Succession Act.
To ensure the preservation of at least part of the succession, the survivor is taken to a safe location away from the event.
Some members of Congress may also skip the event, just in case there is a need for a House or Senate member to take part in a reconstituted government.
NPR says that in recent years, the lucky Cabinet member has stayed in Washington and ordered pizza while he or she sat with a security detail—along with the “nuclear football,” the famed briefcase with the nuclear launch codes.
The idea of the designated survivor even made a cameo appearance on the TV series The West Wing, when Martin Sheen’s character informed the Secretary of Agriculture that he would be sent into hiding.
The fictional president's advice was simple:
“Get your commanders together. Appoint Joint Chiefs, appoint a chairman. Take us to DEFCON 4. Have the governors send emergency delegates to Washington. The assistant attorney general is going to be the acting A.G. If he tells you he wants to bring out the National Guard, do what he tells you.”
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