Johh Doe wrote in :

Bill the Cat wrote:
It is a lot harder for a returning Mars spaceship to get to ISS than
the Earth's surface.

Yes. But consider the size of a mars ship capable of keeping a crew
sane and in good health for 2 stretches of 6 month trips. If you do
not re-insert the big ship in earth orbit upon arrival, then you lose
it all is big fireworks over the pacific (can they plan such a long
trip for exact splash down into the pacific ?

Are you really so unimaginative as to believe that the only two choices for
the Mars ship are "brake into LEO" or "fireworks over the Pacific"?

Has the possibility not occurred to you to leave the main Mars ship in an
Earth-Mars cycling orbit while a small capsule returns the crew to Earth?

If they are serious about quarantine, the quarantine will be done in
orbit with proper equipment. So either you have the equipment on the
mars ship, or the occupants transfer to such a facility in orbit prior
to coming back.

If an off-Earth quarantine is deemed mandatory (and I'm far from convinced
it is), the moon would be far easier to reach from Mars-Earth transfer
orbit than anything in LEO.