What did john brown need in order for his plan to work?

John Brown needed several key elements for his plan to succeed, primarily a significant number of armed supporters to join his cause against slavery. He also required financial backing and resources to equip his followers, as well as strategic planning for the raid on Harpers Ferry. Additionally, he hoped for a widespread slave uprising in the South, believing that the event would inspire enslaved people to revolt and join his fight for abolition.