While it is true that President Lincoln tried to find a peaceful solution to the growing tensions between the North and South, it is highly unlikely that the Civil War could have been entirely negotiated away. The issue of slavery was deeply rooted in the culture and economy of the Southern states, and many Southerners saw their right to maintain their way of life as non-negotiable. Additionally, the seceding states had already taken significant steps to separate themselves from the Union, making it difficult to imagine a scenario in which they would willingly rejoin under any terms. Furthermore, there were radical elements on both sides of the conflict that were unwilling to compromise, further complicating the possibility of a peaceful resolution. In conclusion, while negotiation may have been an attempt by President Lincoln to avoid war, the reality is that the Civil War was a complex and multifaceted conflict that was ultimately fueled by deep-seated ideological differences and economic interests. So, to answer your question, no, the Civil War could not have been negotiated. It was inevitable due to the irreconcilable differences between the North and the South.