My father has a biography that reads a lot like your father's with respect to his service to this nation in World War II combat (U.S. Navy LCI Commander in the Pacific) and his commitment to it for decades following. He has been close to death several times over the last few years and the thoughts and prayers of many friends on this forum helped us through those times.
I know that your father is in a better place now, serving with distinction. I know you will see him again.
All of this reminds me of a saying a like to apply to my father:
"If I can be half the man my father was, and raise my sons to be twice the man I am ... I will have contributed greatly to society."
Again, may the Peace of God, that passeth all understanding comfort and keep you and your loved ones.