It's incredibly hard to send someone into space. It takes tons of money, huge amount of research and it's dangerous to send someone to a place were there body isn't adapted. But we've done it. For the last 50 years we have figured out how to take something as fragile as a human being and sent it into space and expanded the reach of mankind. I see no reason why we can't continue to strive.
I cannot remember who taught me the sentence that is my title. Perhaps it was my father, an engineer who started working with vacuum tubes, and ended working with integrated circuits. Perhaps it was John Glenn, my personal hero. Whatever the source, it is true. When we do research, we find new things. We did not think humans could fly in 1900, or that we could go to the moon in 1950. But this nation needs an aspirational goal to prove to ourselves once again that we can do great things. Going to Mars could be that goal, and could benefit all of us in ways we do not imagine.