Why would WW3 have anything to do with Biblical prophecy? WW1 and WW2 didn't.
Jesus said there would be birth pains before he returns and it would be difficult to find two bigger ones. WW2 led to the rebirth of Israel which is one of the biggest signs that points to the Lord's return.
Yes it's true that every generation believes it's the last, but Israel wasn't around during the previous ones, so that's how we know his return is near.