Dbq; Slavery, Apush

Question: Some historians argue that slavery was the primary cause of the American Civil War. Utilizing the documents and your knowledge of the period 1846-1860, explain to what extent you believe this statement to be valid. Slavery started in America when the colonist traded rum and molasses with Africa in exchange for slaves, this was part of the triangular trading system. From there on many slaves were brought from Africa, their journey is known as the “Middle Passage” which was a horrific journey because half of the slaves died on the ships. Since then there has been endless debate over the causation of the American Civil War. Many different types of historians have argued for and against slavery being the main cause. A historian named Elbert B. Smith wrote, "Slavery worked itself into a constitutional dilemma and became a symbol of disunion which must be destroyed for the salvation of America itself". I myself do believe that slavery was the main cause of the Civil War. As mentioned in Document A, Senator John C. Calhoun says in his speech, “I have, Senators, believed from the first that the agitation of the subject of slavery would, if not prevented by some timely and effective measure, end in disunion.” Since Senator Calhoun was pro slavery, he argue that slavery was the cause for the North and the South to separate, as mentioned in the quote, and have conflicts with each other. Document B talks about the Fugitive Slave Act of 1850 which states that any runaway slave should be catched and returned to their owner. This act also stated that any federal marshal or public official that refused to arrest a runaway slave would be fined and anyone who helped a runaway slave would be sentenced to jail. This document also talks about the Kansas-Nebraska Bill which repealed the Missouri Compromise of 1820 and allowed people in the territories of Kansas and Nebraska to decide for themselves whether or not to allow slavery within their border(popular sovereignty) Both of these acts that were mentioned are an example of the North and the South having disagreements, as Ralph Emerson mentions about the Fugitive Slave Act “required me to hunt slaves,” in this quote when he says required it means that he is being forced to hunt slaves and return them to their owner. Having these disagreements and the North being furious about the Fugitive Slave Act it gave the South and North more reason why to go into a war.
In Document C, William Walker shares his views on the Western Hemisphere. He uses an example in Nicaragua, saying that slavery in that country would “furnish a supply of constant and reliable labor requisite for the cultivation of topical products”. He also believes that the tension between free and slave labor in the United States touches the interest and destiny of those in the struggle and it also would affect the whole continent.
In Document D, it shows a map of what would've been the result of the “Crittenden Compromise.” The Crittenden Compromise of 1860 was an unsuccessful last-minute effort to avert the Civil War. It was proposed by Senator John Crittenden of Kentucky with support from the National Union party. Basically this compromise accepted the boundaries between free and slave states that had been set by the Missouri Compromise of 1820, extending the line to California, and assuring the continuation of slavery. This compromise upheld the Fugitive Slave Law of 1850 with minor modifications, and called for vigorous suppression of the African slave trade. The compromise gained support by the border states but nevertheless, it failed in the House of Representatives. Its defeat made clear the inevitability of the Civil War.