Answer: Parallel structure.
Step-by-step explanation:
A parallel structure is a term used in rhetoric. It refers to a rhetorical device that includes repetition of adjacent sentences (sections of a text). The repeated sentences place focus on the main idea that the author wants to express.
Lincoln uses this device in his Second Inaugural Address, where he explores and compares the expectations of both parties. The purpose is to point out that their desires are of equal importance.