> Expanding human life to Mars (and the entire solar system) is a fantastic goal for humanity.

I think you're underestimating how great Earth is, how awful other planets are, and how big the solar system is.

> I would much rather we advance our technology in the pursuit of Mars than in the pursuit of weapons of war.

Colonization generally does not rhyme with peace. It's very likely there will be conflicts over territories. Space exploration and military production always have been tightly coupled. Where I live the space industry is dominated by "Airbus Defence and Space".