Perhaps the best motivation for going to Mars is political. It is obvious that no single nation currently has either the will or the resources to do it alone, but a consortium of nations and space agencies could achieve it within 20 years.
“If it's true that men are such beasts, this must account for the fact that most women are animal lovers.”
“I have been in a lot of movies, but none of them are critics' darlings, you might say.”