I never know how much credit to give to the speech-writer and how much to the public speaker. I presume that the basic message(s) come from the speaker, but often the reason why they are effective is the way they are presented - which comes from the speech writer.
Does anyone else see the irony is JFK's most quoted speech line..."Ask not what your country can do for you; ask what you can do for your country!"?
His political party subsequently went all-in on buying the votes of Americans with government cash and goodies. They MANIFESTLY ask, "What are you gonna do for me?" at election time.