Treasures being sent away from Earth has shown up in my campaigns too: when things started to look dangerous some museums sent crates outwards, but of course most collections were merely moved to some bunker instead (where they are now nice nests for TITAN nanomachines or resources for Earth survivors). Such caches are of course amazing treasures if they can be validated. The big problem in escaping from Earth physically during the Fall was that rockets and shuttles are very visible and fairly easy targets - they can be seen from ground and space, move in a slow and predictable fashion and it is enough to destroy their aerodynamics even slightly with a laser, missile or debris cloud and they turn into a fireball. Beanstalks are much safer, except that now you are at a key piece of infrastructure together with half of humanity, surrounded by desperate people. But if you have advanced nanotechnology and some resources you can make a "pocket rocket". If the payload is small and doesn't need life support, it can easily be the size of a normal intercontinental missile. Use light and strong nanomaterials, stealth it as much as you can (or launch many decoys/copies), and make sure it can rendezvous with friendly forces. The rendezvous issue might be the real reason the presidential rocket has been out there so long: the original plan had it being picked up somewhere in high orbit by a US spaceship. But that ship got destroyed. And the situation on Luna didn't look good. So the decisionmaking system went for a long-haul approach: use the small course correction engine (say a standard ion engine) to plot a low energy orbit to Mars. Such orbits make use of multiple passes around Earth and Luna to get enough speed to move into interplanetary space, and then similar sequences to get into orbit or aerobrake for a landing. Of course, being the US cabinet on Mars in 10 AF is a bit tricky. It is not just that the nation is gone, the whole system of national sovereignty and international alliances is gone. It is a bit like noblemen of the Holy Roman Empire showing up in the EU ("Go back to Luna, Mr President. They do historical re-enactment there.") Worse, there might be plenty of people who really didn't like the national states (Canon suggests they were pretty authoritarian and nasty in the century leading up to the Fall), as well as various new players who don't want to see anybody rock the boat - no doubt the presidential nose-cone was crammed with top-secret information and codes, most of which is totally irrelevant today but some of which might ruffle a few feathers ("So the reason Monolith - currently Omnicor - got their Mercury base was a secret deal to hide that the CIA had supported the von Braun Argonaut movement! And Professor Al-Shmi was/is a plant?!") I have the picture that many former national governments form a kind of loose network. An exile club not unlike post-Russian revolution exiles talking about the good days, hatching pointless plans and trying to adapt to a world that is utterly unlike what they had. Some turn to drink like the government of East Timor. Some give up and become Titanian microcorps like Sweden. Some might become criminal networks.