I would make Alexander the Great complete his exploration across India, just to see if it would have any impact on the future. Your question reminds me of the 1980's movie "Final Countdown"were a modern warship finds itself back in time on the Eve of the attack on Pearl Harbor and has to decide if they will intervene or not. Always a fascinating topic!
I would have Abraham Lincoln aborted. He sold out the united states country and set the stage for turning the U.S. Into just another totalitarian government. Naturally, like any good politician, he latched onto a popular issue (slavery) to divert attention from his true agenda.
I would ensure that Eugene V. Debs was elected POTUS in his 1912 campaign.
I would change the exit route That R.F.K. Took on the night he was killed.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.