As it happens, the topic of the Magi and the purpose and time of their visit is a personal favorite. An article in our home newspaper which got my attention ran exactly ten years ago. I've shown a CD several times at church which explores information from that article in great detail.
http://www.bethlehemstar.net/

To follow your post, Lincoln seems to suggest that God leads people to do the same thing. According to scripture, God leads people to achieve His purposes, but that doesn't imply that all people act in one accord. For example, the story of Exodus cannot be told without God hardening the heart of Pharoah and leading him in opposition to Moses and the Isrealites. The same may be true of the Civil War, but don't ask me to speculate on that. Wouldn't be prudent. ;-)