Lincoln wasn't the last casualty. There.was still some blood to be shed before the formal end of hostilities and even more during the violent overthrow of Reconstruction. However Lincoln's quotation of Shakespeare is entirely in his character. There's no mind-bending space/time transcendence in this episode, only the sadness of war. It's no wonder that MASH picked up on this one. (note: Jamie Farr has a mini role!)