Answer:
1. The purpose of this speech is to inspire, thus it has an inspirational tone.
2. Kennedy's main vision for space exploration was acquisition of knowledge; he strictly opposed anything else when he stated that "we have vowed that we shall not see weapons of mass destruction, but with instruments of knowledge and understanding."
3. Kennedy implied that space would become a war ground and not a place of peace and learning if the Soviet Union were to come "first" in space.
4. Kennedy compared space to an ocean because both were once new, uncharted territories waiting to be explored. By making this comparison, he implies that space is the object of America's next conquest.
5. Kennedy's statement "We chose to go to the moon in this decade" may have became so well-known because it represents one of the greatest achievements of the United States and the human race as a whole.