Star Trek has one of those artifacts in the fact that we've caught up to history and there's been no Eugenics Wars or World War 3 (so far), so it's a bit hard to fit it in. Trek is an alternate universe to the hardcore Trekkies while the producers generally just prefer to do time travel showing "our" future. There's no way to thread that needle, sadly, so you just have to accept it.
I did note that before Khan PHYSICALLY showed up, Scotty and other enlightened humans thought he wasn't that bad of a guy by comparison. Sort of like Napoleon defenders.
I did note that before Khan PHYSICALLY showed up, Scotty and other enlightened humans thought he wasn't that bad of a guy by comparison. Sort of like Napoleon defenders.