The figure of speech used in the above lines from President Obama's speech is Parallelism. It is basically repetition of same kind of words, clauses or phrase to make the desired effect
The use of parallelism, or the repeating of grammatical features, is essential for both effective writing and public speaking. Both the grammar of sentences and the overall organization of thoughts are impacted by parallelism.
The repeating of grammatical elements in a text to produce a pleasing effect is known as parallelism. The exact same words are sometimes repeated, as in the sayings "easy come, easy go" and "veni, vidi, vici" ("I came, I saw, I conquered"). In other cases, it entails repeating the structure, meter, or meaning.
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