Asbestos was used for decades before it filled his lungs, but he took the word of the US chemical industry too readily when they gave him their assurances on the harmlessness of Agent Orange. The consequences, including the loss of his son, never completely gave him peace for the rest of his life.
One little event you'll enjoy: in 2014, we were invited to join the Zumwalts for the christening of the first of the new Zumwalt class of destroyer at the Bath Iron Works in Maine. Some attendees were given honorary "Skipper" hats, usually only worn by the ship's captain (his name was really Captain James Kirk!). So, we were wearing them in the Portland airport, on the way home after the ceremonies. A young woman saw them, and ran up to us, and asked us (including his daughter and granddaughters!) if we had any connection to Admiral Zumwalt. When we said yes, we did, she told us that the man she worked for also knew him well, and was still obsessed with his great humanity. We said that was nice to hear, and by the way, who DID she work for? His name was Bill Clinton.