Post-Apocalyptic Presidency?

The armed forces question got me thinking:

Suppose a president orders a full nuclear strike against our enemies…riding out the aftermath in Air Force One or some secret bunker…and his term as president ends after a few years or so.

There isn’t much of a government left, let alone a civilian population.

Is there some secret emergency clause that extends his presidential authority indefinitely, say, until a working government and voting infrastructure is reestablished?

The president has the power to declare martial law in a wartime situation. I presume this power derives from his/her role as Commander in Chief, since it isn’t explicitly mentioned in the Constitution. I believe Lincoln declared martial law during the Civil War, and FDR placed national security ahead of civil liberties during WWII with the Japanese-American internments. So a post-apocalyptic prez, assuming he/she is still alive, would probably do something similar, although I don’t know if anyone would pay attention.

Don’t forget that the country will still exist even after a nuclear war. Most of it’s major cities would be destroyed, but the people living in rural areas (and probably most of the suburbs) would still be alive. Assuming that we haven’t been invaded and conquered, the survivors would form new state governments, who would nominate people to re-stock Congress. Congress’ first actions would almost certainly be to impeach, remove, and lynch the president who got us nuked.

“Assuming that we haven’t been invaded and conquered, the survivors would form new state governments, who would nominate people to re-stock Congress”

The military would be the ones to do this and get it started. Afterwards if everything went well then it would be turned over to the people to finish

One of the less publicized functions of the Federal Emergency Management Agency is to ensure that the government would not stop functioning.

The Pres, VP, cabinet members, and at least one Congressman from each state would go one of several hardened locations, and would survive.