Well the thing about Jurassic Park that is lost in the movie adaptation, is that John Hammond was a megalomaniac who (in my opinion) thought he was a god. He didn’t think anything he did was wrong nor that anything could go wrong for him.
The Ending
He and Ian Malcom get killed by a pack of compsognathus trying to get in the helicopter leaving the park.
A reminder that he is wearing a “Occupy Mars” shirt. A movement to occupy Mars. How can we do this? Well we need water. And he wants to bomb Mars to achieve this. The Nazi supporting lunatic wants to bomb Mars!!!