Much of President Kennedy’s pithy 1,366-word inaugural address, delivered on January 20, 1961, was well-written and meaningful, but as often happens, his speech has stood the test of time thanks to one perfect phrase. Amidst an address filled with both hope and dire warnings (“Man holds in his hands the power to abolish all forms of human poverty and all forms of human life,” the latter being a clear reference to atomic weapons), he issued a direct appeal to Americans everywhere to stand up for their country. You know the line:

“And so, my fellow Americans: ask not what your country can do for you — ask what you can do for your country. My fellow citizens of the world: ask not what America will do for you, but what together we can do for the freedom of man.”

Source : https://www.jfklibrary.org/learn/about-jfk/historic-speeches/inaugural-address