No, the ‘root’ of the civil war was the irresponsible ‘fire breather’ democrats led by Vice President John C Breckenridge.
The Republicans bent over backwards (Corwin amendment) to maintain the Union.
Think how different those four years had the Democrats used their incredible levels of power in Federal government to peacefully secede.
The belligerent democrats had more than sufficient power in the House, Senate and Judiciary to force the Federal government to accept the their leaving.
The elected not to go that route, but to secede. Then the belligerent democrats forced the issue (on dithering Virginia) by starting a shooting war at fort Sumpter.
Maintain their control over the money flowing into the country through European trade from Southern products.
72% of all trade was produced by the South, and therefore 72% of all Washington DC's tariff revenue came from Southern export products.
Additionally, the powerful Northeastern elite "robber barons" had rigged the government laws to provide them favorable protectionist laws, and this forced the Southern states to buy their products and utilize their shipping, banking, warehousing, insurance and other services.
Articles I have read assert that 60% of all the revenue produced by the South ended up in the pockets of New York and Washington DC elites.
They started the fight to protect their own money, not because they gave a sh*t about slavery.
We know they didn't really care about slavery because they passed the Corwin amendment through a Northern controlled congress and this amendment would have made slavery permanent.