Did all of those people need to die in a bloody Civil War? No, the war didn't HAVE to happen, but were those deaths the fault of Lincoln? not necessarily. Why would it make sense to put all of the blame on Lincoln, for the bloodshed and death toll in the war, but not put the same blame on Jefferson Davis? It was actually the Confederates who attacked first, at Fort Sumter, so it was not Abraham Lincoln or the Union military which initiated the armed conflict. Some have said that slavery was a national institution, and not just a thing of the South, in order to claim that slavery was not the cause of the Civil War. It is true that slavery existed all over the Union, but by the time Lincoln became President, only four of the 26 states which would remain loyal to the Union, still had legalized slavery: Missouri, Kentucky, Rhode Island, Delaware; and many of the Midwestern and far western states, never had legalized slavery during their history as States.
Many argue that Lincoln was a tyrant, based on the idea that other nations had ended slavery without civil wars, usually by paying money to the plantation owners. This is a misnomer, not only because political and social conditions of the US were unique, but because the Southern States did not even give Lincoln and his administration a chance to do anything like this, since they seceded before he even took office. Also, someone argued that Lincoln could have freed slaves in the North, in order to avoid bloodshed. This is a funny argument from people who criticize Lincoln for overstepping Constitutional boundaries, and then say he should have outright declared slavery illegal. It took the passage of the 13 amendment to make slavery illegal, and even then, Lincoln and others had to do a lot of wrangling to get it passed. Furthermore, there is no reason to believe that the Southern leaders would have ever even entertained this idea, since they were so paranoid in their perception of Lincoln's plans toward slavery, that they did not even allow his name to put on the voting ballots. Lincoln did not cause the Civil War, and the Union did not start the armed conflict. It is not rational or logical to put all of the blame for the carnage of the war on Lincoln, and not, at the same time, put blame on the Confederate leadership; especially since the Confederacy fired the first shots.