Final answer:
John Brown tried to capture Harper's Ferry to capture its arsenal and distribute the guns to local slaves. It was a dramatic gesture to point out the moral abhorrence of slavery.
Step-by-step explanation:
John Brown tried to capture Harper's Ferry to capture its arsenal and distribute the guns to local slaves. By arming the slaves, Brown believed he could incite a rebellion and overthrow the institution of slavery. This act was seen as a dramatic gesture to point out the moral abhorrence of slavery.
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