It was put to a local vote.
By allowing the people of each new state to vote on whether it would be a slave-state or free soil. That sounded reasonable enough. But if only one state was voting at a time, that one state would attract every terrorist from both sides to try to influence the vote. That's what happened in Kansas - and the result was called 'Bleeding Kansas'.
Mississippi was a slave state until the end of the Civil War.
Slave state
Yes, Texas was a slave state.
Slave
the kansas- nebraska act
It was delayed because the issue of Slavery and to balance whether it should be a free or slave state.
Because of the balance in Congress.
No, the Missouri Compromise did not involve whether the Missouri River would be the border of the state. Instead, it was an agreement made in 1820 to address the balance of free and slave states in the Union. The compromise allowed Missouri to enter as a slave state while Maine entered as a free state, and it established a line at latitude 36°30′ north to determine the future status of slavery in other territories.
It rose the question of whether each new state entered would be a slave state or a non-slave state. They needed to keep the slave states equal to non-slave states.
What do you mean by "safe"?
Growing sectionalism was illustrated.
Popular Sovereignty
The Kansas-Nebraska Act of 1854
The principle of letting the people of a new state vote on whether it was to be a slave-state or a free state.
The US Congress passed the 1854 Kansas-Nebraska Act called for the use of popular sovereignty to determine whether a territory would enter the Union as a free or slave state.
Because Congress reflects the wishes of the nation as a whole.