When Abraham Lincoln took office as the 16th president of the United States in March 1861, the country was already deeply divided over  slavery and states' rights. Some southern states had already seceded from the Union, and the threat of further secession was high. 

 Although Lincoln was in favor of preserving the Union, it is unclear whether he privately believed that he could have prevented the outbreak of the Civil War. In his first inaugural address, he acknowledged the seriousness of the situation and the possibility of war, saying, "There seems to be a fear among the people of the Southern States that  their property and their peace and personal safety will be under a Republican administration. There has never been any reasonable cause for such fear. Indeed, the most abundant evidence to the contrary always existed and was open to them. It can be found in almost all of his published speeches that are now speaking to you." 

 But Lincoln also expressed a willingness to use force to preserve the Union, saying, "I have no intention, express or implied, of interfering with the institution of slavery in those states where it exists. I do not think I have a legal right to. do so, nor am I inclined to do so. Those whom I nominated and elected  did so knowing full well that I had made this and many similar statements, and  never retracted them; moreover, they placed my approval on the platform. . . , and lend to himself and to me the clear and emphatic resolution that I now read: "Resolved, That detention violates the rights of states, and especially the right of each state to organize and control its own internal institutions. 

According to his discretion is essential to that balance of power, on which depends the perfection and durability of the political structure; and we condemn the illegal invasion by armed force of the soil of any State or Territory, on whatever pretext. among the most serious crimes. I will now repeat these opinions, and thus call general attention only to the most convincing evidence, where the case is delicate, that the property, peace, and safety of any part are not at present endangered. Administration." 

 Then, the Civil War broke out just over a month after Lincoln took office, and he was forced to accept the enormous task of leading the Union through the conflict. While Lincoln may have hoped to prevent war, he was also willing to do what was necessary to preserve the Union, even if it meant the use of force.