Top three rhetorical devices that were the most effective in JFK's Inaugural Address?

JFK delivered his inaugural address on January 20, 1961. His speech was carefully crafted with the help of a few of his closest advisors. So how did he use rhetorical devices (techniques a speaker uses to persuade or sway an audience to agree with his perspective) to appeal to his audience? Let's go over the key points, and you can choose which three you'd like to write about.
Brevity: at 1,355 words, the speech was relatively short. He held the audience's attention because he wasn't speaking for very long.
Phrasing and diction: in the interest of clarity, JFK intentionally used short phrases and short words. These are three separate lines from the speech:

The world is very different now.
This much we pledge—and more.
We dare not tempt them with weakness.

Repetition: Kennedy repeated key words again and again to strengthen his message. Look at the structure of the speech. many lines begin with the same phrase:

Let both sides explore what problems unite us . . .
Let both sides seek to invoke the wonders of science . . .
Let both sides unite to heed in all corners of the earth the command of Isaiah . . .

Rhetorical questions or ideas: these involve the audience, making them consider their own positions instead of just listening passively.

And so, my fellow Americans: ask not what your country can do for you—ask what you can do for your country.

Flattery: JFK makes his audience feel good about themselves by using complimentary language.

The torch has been passed to a new generation of Americans—born in this century, tempered by war, disciplined by a hard and bitter peace, proud of our ancient heritage . . .