President Nixon greets Apollo 11 astronauts, left to right, Neil A. Armstrong, Michael Collins, shoulders only, and Edwin E. Aldrin, Jr. (Credit: NASA/Apollo)

It’s easy, amid the celebrations of the 50th anniversary of the Apollo 11 moon landing, to see it as an inevitable success. NASA had been preparing for the task for years, ever since President John F. Kennedy made his famous speech at Rice University in 1962, declaring America would “go to the moon in this decade.” When Neil Armstrong