Having done a lot of reading recently on the Apollo program, I found this WSJ op-ed to be a seriously plausible description of how we get to Mars:
1) one rocket sends unmanned capsule to Mars orbit with enough fuel for trip home (this is the lunar equivalent of the command module that did not go to the surface);
2) second rocket delivers to Martian surface a payload of chemicals that would use local materials to build up sufficient rocket power strength to ascend off the surface at Mars mission's end;
3) third rocket sends two astronauts to Mars, they land near ascent vehicle, spend 18 (!) months on surface, then ascend up to command module, dock, and fly that home.
Basic point of piece: enough of the near-Earth stuff! Let's get NASA back in the business of exploration and let the private sector work the near-space commercial.
Couldn't agree more, and like the logic of the mission plan.