It's a popular premise that this election cycle and the division is at unpecidented levels. That is only because we use our own life experiences as if they are the entire scope of history. What we are seeing today is remarkably like we have seen several times before. Those who actually were involved in the campaign cycle in 1976 and 1980, the political establishment was in full war mode against Ronald Reagan and his supporters. As such we were castigated as troglodytes who the party needed to purge from their ranks. In fact in many cases it's exactly the same people saying exactly the same things about Trump and his supporters today.
However it goes back further, if you look at the 1860 election the political professionals were appalled at this classless backwoods rube who emerged as the candidate. The Ameeican people were so divided that almost half left the country and a full fledged war ensued. In the 1860 Republican Convention the favorites were Senator Henry Seward, Ohio Governor Salmon P. Chase, or St. Louis judge, Edward Bates, and Simon Cameron from Pennsylvania were all the ones being watched to emerge as the nominee when an abscure Abraham Lincoln got the nod. Lincoln brilliantly brought all the competitors into his cabinet, even though they all thought he was a fool. After some very bumpy and disloyal, even insubordinate acts by them, they eventually came to understand the merit of his leadership and together successfully steered the ship of state during our nation's most dangerous times.
If you go back to our first time where we saw duplicitous actions by party leaders against their own candidates and outright lies pushed by the opposition against a candidate was our very first contested election with John Adams seeking reelection against his Vice President Thomas Jefferson. It was one of the dirtiest elections in history. Thomas Jefferson and Alexander Hamilton formed and led the two political parties while serving as Washington's cabinet until the infighting became so severe that Secretary of State, Thomas Jefferson resigned and moved back to Monticello. When Secretary of Treasury, Alexander Hamilton stepped down he stacked Washington's Cabinet with his lackies who did his and his Federalist Party's bidding.
John Adams, with hopes of unity, kept Washington's Cabinet which kept Hamilton's voice loud in the chamber. Adams wouldn't give in to Hamilton and eventually fired his left over Cabinet. Hamilton set out to destroy his own Party's candidate to get back at Adams. Hamilton, long the prolific writer, he would be considered a blogger today, wrote the campaign pamphlet against his own Federalist President "Letter from Alexander Hamilton Cconcerning The Public Character Of John Adams, Esq. President Of The United States." 24th of October 1800, the first October Surprise.
Hamilton called ro question Adam's sanity, temperament his judgement his morals and his loyalty to his country.
Thomas Jefferson, who Adams and his wife Abigail had considered their best friend until they learned how politics was more dear to Jefferson than personal attachments. Jefferson hired James Callendar, who was what would be considered a yellow journalist today, to write articles to destroy the political careers of John Adams and also his political enemy Alexander Hamilton. The funniest story to go with this is that after Jefferson won, Callendar expected a job in his administration as a reward. When Jefferson cut off access to Callendar, he got his revenge by exposing the world to the story about Jefferson's sexual relationship and children with his slave Sally Hemming.
So you can see that this is nothing new in 2016. However it is much like some of the most turmultuous four election cycles in our history. We have seen that never does the current establishment power structure give in quietly.