The country was breathing. Over the next three years, the compromise seemed to resolve almost all differences. The new Fugitive Slave Law, however, was an immediate source of tension. It deeply insulted many northern countries that refused to participate in the arrest of slaves. Some have actively and violently impeded their application. The Underground Railroad has become more efficient and bolder than ever. Although the compromise operation had the effect of destroying the immediate divisions caused by the Missouri issue, it exacerbated the larger regional conflict between North and South. It served the North that not only did the countries of the South have no intention of ending slavery, they want to expand their presence. In the South, there was growing belief that the countries of the North were using slavery as a wall of fog, behind which they could revive the federalist party and strengthen the central government at the expense of state rights. For nearly 30 years, the compromise worked, with the inclusion of two states together, a slave, a freer one. Then, in 1850, California was admitted as an autonomous free state, which reflected the 16-15 balance, in exchange for a guarantee from Congress that no restrictions on slavery would be placed on the territories of Utah or New Mexico and the passage of the Fugitive Slave Act, which required citizens of all states to return all slaves to their masters.
In 1857, the U.S. Supreme Court ruled that Congress did not have the right to prohibit slavery in the territories as part of the Dred Scott decision. The Kansas-Nebraska Act of 1854 repealed the 36-30 demarcation line for slavery in the Louisiana Purchase area. The following summer, considerable public opinion was gathered in the North in support of Tallmadge`s proposal. Much of this anti-Missouri atmosphere, as it was called, was born out of the true belief that slavery was morally false. Political opportunity has been mixed with moral convictions. Many prominent anti-Missouri men had been active in the federalist party, which appeared to be in the process of disintegration; she was accused of looking for a problem to rebuild her party. Federalist leaders of the anti-Missouri group have pushed some northern Democrats to reconsider their support for the Tallmadge amendment and to support a compromise that would undermine the federalist party`s stimulus efforts. Henry Clay, a congressional leader, played a crucial role in mediating a two-part solution, known as the Missouri Compromise. First, Missouri would be admitted to the Union as a slave state, but offset by the accession of Maine, a free state that wanted to be separated from Massachusetts for a long time. Second, slavery should be excluded from all new states of Louisiana Purchase, north of The Southern Missouri border.
Citizens on both sides of the controversy felt that the compromise was profoundly wrong. Yet it took more than thirty years for the Kansas-Nebraska Act of 1854 to find that new states north of the border deserved to be able to exercise their sovereignty in favour of slavery if they wished. Most white Americans agreed that Western expansion was essential to the health of the nation.