To the airlines, passengers are merely inconveniences that interfere with the proper ordering of airplanes at their assigned airports.
I suspect it is likely that damage from cosmic rays will permanently preclude human voyages to Mars unless a prohibitive weight of shielding is included on the spacecraft.
Why would anyone want to colonize Mars? Antarctica or the Greenland ice cap are much more pleasant environments, and easier to get to as well, and nobody wants to colonize them.
Anyone who thinks we should colonize the moon (or Mars) should explain why they don't want to colonize Antarctica instead. The climate is warmer, there is oxygen to breathe, no radiation, no...
This makes so much common sense that I am sure the Pentagon will never consider it!