The entire attraction of a mars colony is the 3 month to 2 year response time for physical retaliation. Antarctica is still within range of ICBMs, heck even the moon is in range of a modified one. Though the moon is still 3 days away, that is not really time enough to construct a response to a launch. Mars on the other hand, if the event provoking retaliation is right after the Earth-Mars transfer window closes, has 2 years to prepare.
The entire attraction of a mars colony is the 3 month to 2 year response time for physical retaliation. Antarctica is still within range of ICBMs, heck even the moon is in range of a modified one. Though the moon is still 3 days away, that is not really time enough to construct a response to a launch. Mars on the other hand, if the event provoking retaliation is right after the Earth-Mars transfer window closes, has 2 years to prepare.