A Rational Defense of Manned Spaceflight

As computers have become more advanced, faster, and more capable, the arguments in favor of manned spaceflight have become weaker, and space travel has increasingly become the domain of machines.  Long before the invention of the microchip, Isaac Asimov proposed exactly this, describing unmanned, computer-controlled space exploration vehicles that would be able to venture into territories too extreme and too dangerous for humans.  That vision has come to pass, and it is now commonly argued that humans are indeed too soft, vulnerable, and unreliable to utilize in spaceflight, and that removing them from the paradigm removes the weakest link.  Manned spaceflight has largely been relegated to an oft-maligned holdover of Cold War international competition and patriotism.  This is a mistake.