It might have been on Netflix (we cancelled Netflix a while back). It was about how the US gov supposedly has a designated survivor picked out to sit out events where the entire Congress, etc is attending. In the show, all of Congress and the President, everyone, are attending something, and the building is bombed. And this "designated survivor" is then in charge of picking up the pieces and restarting the government. Interesting concept. Even more interesting in today's times.