See sample answer below.

Both paragraphs condemn petty bickering between nations in the face of crisis; in the first, Kennedy expresses a hope that the United Nations will continue doing productive work for peace, rather than becoming a “forum” for nations to insult each other, and in the second, he implores his audience to “explore what problems unite us instead of belaboring those problems which divide us.” His word choice emphasizes the damage unnecessary negativity does, as well as the general childishness and uselessness of such conflicts.

See sample answer below.

Suggest that people are in danger: “strengthen its shield” (285), “split asunder” (284), “iron tyranny” (284)
Inspire people to stand up for what they believe: “give testimony” (286), “casting off the chains of poverty” (284)