Why are you (and everyone else) so obsessed with mars? Legit question.

A Mars base opens up the entire solar system. One of the big problems with sending anything from point A to point B in the solar system is fuel constraints, and fuel constraints are mainly due to:

1) currently only being able to get fuel on Earth

2) Earth's strong gravity

To get a tank of fuel to low Earth orbit, you need to expend many times that fuel's mass is even more fuel, and thus bigger fuel tanks, and thus even more fuel to lift that mass, etc etc etc. The rocket equation is a cruel mistress in 1G.

Mars has everything needed to produce fuel and oxidizer, for either hydrolox or methalox engines. Abundant CO2, water, and it's still close enough to te sun for solar power to be useful. But the kicker is that Mars has about 1/3rd the gravity of Earth. Mass-produced and cheaply-lifted-to-Mars-orbit fuel means that anything launched from Mars orbit doesn't need to ride low-energy time-consuming Hohmann orbits. Want to sent an orbital probe to Pluto in 3-4 years? No problem. Build a big dumb two-stage methalox booster in Mars orbit, put the probe on the front, and fuel it cheaply from Mars' based depots. A Mars fuel-production base opens up the entire solar system to science.