But as I grew into adult life, and visited more than one country here on Earth, I began to think that it is an even higher and more challenging ambition to go somewhere you are not constrained to go by desire for fame or for riches or for being the first in a new territory, but rather by a desire to solve intractable problems. Solving a problem of long standing is a bigger achievement than solving a problem that is unsolved mostly just because no one has found it worthwhile to solve it. Making any of the world's poorest countries richer in general, or making any of the world's most oppressed countries freer in general, is a problem for which some example solutions exist, just as traveling to other planets has some precedent in the manned moon missions and in robot space probes, but I suggest it is actually a much tougher and more interesting problem, a problem more worthy of a gnarly man willing to risk his life. I still admire astronauts, and I've exposed all four of my children to books and films about space exploration, but I'd be even more thrilled to see them or other young people I know take on the exploration challenge of bringing about improvement in the lives of their fellow human beings in the worst-off parts of planet Earth. There is a lot of challenging science involved in those problems, and the contributions to human knowledge that will come from solving those problems will provide lasting benefit to all of humankind, whatever planet our descendants live on.
AFTER EDIT: Two comments below mention "paternalism." Nope. I am talking about "fraternalism," sharing in the life of the people where you live, understanding their problems deeply because they become your problems too, and then building solutions from the neighborhoods you live in. You can't jet-set that in, and you can't phone it in or international consultant it in, you can only live it in. I've asked before here on Hacker News how many of the participants here have ever even lived in (not just visited, but lived in) a third-world country. Not many have. (I have, and it was a dictatorship when I lived there, and as a foreign national I was part of the process of nudging it to become the democracy it is today.) To be a brother of your fellow human beings is a great adventure. It's harder than armchair criticism, but also more challenging and interesting.