Trump claims Civil War didn't have to happen: "You could've negotiated that". Lincoln repeatedly offered compensated emancipation to the South through 1861 and 1862. The famous "as our case is new" quote from December 1862 was offered in support of a scheme for compensated emancipation.

In April 1862, President Lincoln actually signed into law a plan of compensated emancipation for the District of Columbia. The reveal here is that someone is marinating Trump's dim old brain in pro-Confederate pseudo-history. The historical record is clear on Lincoln's various reparative attempts. Moreover, Henry Clay's entire public life was chiefly devoted to striking such a "deal." [Un]Ironically, it was business interests in the South that continually thwarted Lincoln's every effort.
https://www.abrahamlincolnonline.org/lincoln/speeches/congress.htm#:~:text=As%20our%20case%20is%20new,remembered%20in%20spite%20of%20ourselves