Which figure of speech is used in this text?
We are not destined to be adversaries, but it is not guaranteed that we will be allies.
—President Bill Clinton, speech to the Russian parliament

 - antithesis
 - apostrophe
The text uses antithesis, the contrasting of opposing ideas within a parallel grammatical structure.
Clinton contrasts two clauses, we are not destined to be adversaries and it is not guaranteed that we will be allies.