Von Braun lived just long enough for the first Viking lander. So he got to hear the bad news.
Landing heavy objects on Mars is not quite as bad as an airless landing, but it still takes a lot of fuel. Von Braun probably would have wanted to build a large space station orbiting Mars, with rockets shuttling back and forth from Earth orbit for supply. Then, with enough fuel accumulated in Mars orbit, a soft landing on rocket power would be possible.
Landing heavy objects on Mars is not quite as bad as an airless landing, but it still takes a lot of fuel. Von Braun probably would have wanted to build a large space station orbiting Mars, with rockets shuttling back and forth from Earth orbit for supply. Then, with enough fuel accumulated in Mars orbit, a soft landing on rocket power would be possible.