What invention helped lead to the Civil War?

The cotton gin invented by Eli Whitney helped lead to the civil war in the sense that it made cotton easier to harvest. Demand for cotton was always high both for Northern textile mills and for those abroad. To meet demand, the southern US states therefore imported more slaves. Slavery became an issue in antebellum America and was discussed in the construction of the US Constitution. Many Northern people believed it to be immoral and did not want it to spread to the new US territories.