We are living in a fortunate time in history as the price of space exploration is coming down in rapid fashion, bringing other celestial bodies within touching distance from us.   It's literally a once-in-a-million-years opportunity.  

Beyond us humans, expanding our presence is also a life insurance for the life on Earth.  However, Mars is not just a Planet B where we can escape if things go wrong here. For the humankind, there are even greater reasons.