Mars as our future home

From the New Yorker: "One of these days, we may well do ourselves in; certainly we're already killing off a whole lot of other species. But the problem with thinking of Mars as a fallback planet (besides the lack of oxygen and air pressure and food and liquid water) is that it overlooks the obvious. Wherever we go, we'll take ourselves with us. Either we're capable of dealing with the challenges posed by our own intelligence or we're not. Perhaps the reason we haven't met any alien beings is that those which survive aren't the type to go zipping around the galaxy. Maybe they've stayed quietly at home, tending their own gardens."