It’s a very well-known and regarded speech – it’s the “Ask not what your country can do for you, but what you can do for your country” speech, after all – so it’s interesting to see it deconstructed and realise why it is so effective.
For example, he used contrasts (of which “Ask not…” is only the most famous example) multiple times in the speech. So much, in fact, that the article says it worked out at an average of one use of contrast per 39 seconds of speech.
President Kennedy also used a great deal of imagery which gives the speech ‘altitude’ as speech writer Sam Seaborn from The West Wing would put it. “Casting off the chains of poverty”, for example, is a powerful image which excites the imagination.
The study of rhetoric used to be one of the major components of education throughout the classical and medieval periods. While it’s obviously less important than subjects like maths and science, I think we do lose something by not really understanding rhetoric. A speech like this is inspiring and though it’s true that it would lose that to a degree if we all understood more about the techniques being used, I do think it would be beneficial if we understood better exactly how politicians are manipulating us!