This is something my history teacher suggested to me in High School: If the Union won the First Battle of Bull Run, the South would've decided that they couldn't win the war and negotiates an end to the war with the Union. Another POD is that the South still wins the First Battle of Bull Run, but the battle isn't as bloody as in OTL. As such, the Union is more willing to negotiate with the South. My question is, how likely is either timeline? Will Lincoln be able to win reelection in 1864? What happens to slavery?