Detailed Instructions: This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Q: Passage: The American Civil War caught both sides unprepared. The Confederacy hoped to win by getting Britain and France to intervene, or else by wearing down the North's willingness to fight. The U.S. sought a quick victory focused on capturing the Confederate capital at Richmond, Virginia. The Confederates under Robert E. Lee tenaciously defended their capital until the very end. The war spilled across the continent, and even to the high seas. Most of the material and personnel of the South were used up, while the North prospered. Question: What was the Union's original war aim?
A:
capturing the Confederate capital at Richmond, Virginia