", capable of launching 120 tonnes to Earth orbit or sending payloads in the 40 to 50 tonne
class on direct trajectories TO THE MOON or Mars"

Chris, we simply do not have the votes right now for manned Mars flight.

And that's okay, as there's a pressing need to set up telescopes on the Moon to deal with the impact hazard - and yes, these can be justified on a cost/benefit basis. And those in turn could hold the manned space infrastructure in place until public support for manned Mars flight rises to the point at which it can be done...

Now whether the EELVs or Shuttle C is used for these telescopes is almost irrelevant - Bob can either re-work in-stiu propellant production for medium lift launchers, or figure out how to evolve them in heavy launchers - the important thing here is the total manned space infra-structure, and by the way, the station is developing that quite nicely...

ep