It led for the citizens of each state to decide whether or not their state would be a free or slave state. Although it did backfire with events such as bleeding Kansas
Honestly I think it's because the polls said clinton was gonna win by a landslide so I think people got comfortable. pollsters call people and ask who they're voting for and I don't think many people want to admit they're voting for someone like trump so the numbers were wrong.
It was Political upheaval
Answer:
I think it's Gutenberg's press.
Hope it helped.
He wanted to redraw the border of countries.