Most people who grew up in the 1960s cite two events they can vividly remember. The first is when President John F. Kennedy was assassinated in 1963. The other is when the U.S. landed on the moon in 1969. I will never forget the day Kennedy was killed. But another memory takes precedence over the moon landing for me. It took place two years earlier in 1967, when a Cape Town surgeon — Dr. Christiaan Barnard — performed…