How did the Union finally collapse into civil war?

Answer 1

Through the failure of the various compromises about the admission of new slave-states that had been attempted over forty years.

When Lincoln rejected the final one (because it would have allowed some extension of slavery), the war was on.

Answer 2

The Union, the United States, had sectional differences. These were primarily focused on the perceived marginalization of the Southern slave states and the Northern states that were not economically driven by slave on the huge cotton and tobacco plantations in the South.Although slavery was protected by the US Supreme Court decision of 1857, the South held minority positions in the US Congress. The fuel to the fires of secession was the election of Abraham Lincoln to the US presidency. The Republican Party had been formed when the Whig Party dissolved in the early 1850's.

Anti-slavery Whigs formed a new political party dedicated to the abolition of slavery in the US.

The failure of the predominating national Democrat Party to field a single candidate to run against the Republicans resulted in three separate parties. With only 41% of the popular vote, the Republicans won the US presidency with an overwhelming victory in the Electoral College.

President-elect Lincoln was a moderate Republican. He realized that abolishing slavery as a one time act was impossible and not a wise move as it would create economic, social and political chaos.

He also knew that slavery was at the present time legal.

Lincoln was personally against slavery, but he saw a higher duty. That duty was to keep the US a united country. He did all he could to let Southern slave interests understand that he had no plans to interfere with slavery where it already existed. He also promised to enforce the 1850 Fugitive Slave Act.

Lincoln was a Unionist, he was not an abolitionist.

From November 1860 to March 1861 radical Southern Democrats began to create secession in the South. It was a state by state process.

Under President Buchanan, a Democrat and Virginian, he allowed Federal forts and other Federal property be peacefully taken by the radical "Confederates". By March 4, 1861, seven Southern states had seceded and formed the Confederate States of America.

When Lincoln was sworn in as US President on March 4, 1861, he headed a nation divided in many ways. There were many Northern views on the main issue of the day. These were slavery and western expansion.

Most Americans in the North were not abolitionists. Many if not most did not wish to see the expansion of slavery westward.

Many Northerners were quite separated on the issue of slavery. Fisherman in Massachusetts for example had no interest in the slavery issue.

Many Northern Democrats had "problems" with the radical wing of the Republican Party. The largest US city, New York City was a Democratic stronghold.

There appeared to be a "stand-off" on the secession problem. Owners and employees of Northern textile factories saw a problem if the cotton farmed in the South became a resource controlled by the Confederacy. The industrial North had every motive to keep the status quo.

When Lincoln took office only 7 of the slave states had formed the Confederacy.

eight other slave states had not joined the Southern rebellion.

When radical secessionists demanded the surrender of Fort Sumter in the Charleston Harbor in South Carolina, its Commander refused.

This Federal fort was US property and Lincoln was sworn to 1. Keep Federal property safe; and 2. to keep the US unified.

The bombardment surrender of the fort forced Lincoln to ask for 75,000 volunteers to serve 3 months. The goal was to end the rebellion.

At this move, 4 other slave states joined the Confederacy. The armed conflict began and no one at all could have foreseen the disaster that the failure of compromise would bring.

The US Civil War was the worst failure of the United States in the brief history of the nation.