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.
“James Bond is quite serious about his drinks and clothing and cigarettes and food and all that sort of thing. There is nothing wry or amused about James Bond.”
“Men are beginning to realize that they are not individuals but persons in society, that man alone is weak and adrift, that he must seek strength in common action.”