There was a bit of comparative calm that settled in, from the immediate time after the Civil War, until the late 1960s. The level of ugliness of ideological attacks that Franklin Roosevelt saw, for example, were nowhere near what Obama & Trump have seen. That century was a far calmer era for political vitriol, than the 1780-1860 time frame, or since the late 1960s.
A not amusing Civil War era example:
"In 1856, U.S. Sen. Charles Sumner of Massachusetts gave a speech criticizing pro-slavery southerners. Three days later, he was beaten so badly - on the Senate floor - by U.S. Rep. Preston Brooks of South Carolina that he didn’t return to the Senate for three years."
[1] https://www.theatlantic.com/national/archive/2011/09/the-ori...
In the 1980s the media hated Reagan about as much as they hated Bush or Trump. Before that it was Nixon. But you really only heard about it if you watched the evening news, and that was 30 minutes of the day. It wasn't being fed to you continuously like an intravenous drip on your phone.
It's the speed and pervasiveness that have increased, not so much the partisanship.
While I wasn't mature enough then to form my own opinion about it, I'm under the impression that the media was also more restrained and professional back then. Now it seems a lot more tabloid, generally. There also seems to be a burring between "opinion/editorial" and reporting, especially online, which fuels the polarization.
And of course a lot of this wasn't entirely unfounded. Mr. Obama really was the first anti-American president; Mr. Bush really was incompetent; Mr. Clinton really was a perjurer, philanderer, power-abuser & possible rapist; Mr. Reagan really did lie a lot (e.g. Iran-Contra); Mr. Carter really was incompetent; Mr. Nixon really was a crook; Mr. Johnson really was a crook &c. &c. &c.
The fact that we keep on electing compromised, power-hungry people to a position of extreme power is no doubt part of the problem, but even back when the presidency was far weaker you had the partisans of Jefferson & Adams maligning one another with language we would be shocked at today.
The only recent American president I can think of who was mostly decent was probably Gerald Ford, who never ran for the position. Maybe that's the secret.
It's said that Trump is terrible with journalists (he is). And there's Obama's quiet, terrifying war on journalists with the Espionage Act, that the partisans on that side almost entirely ignored.
Assisting in the destruction of Syria and Libya is a fine thing to ignore (one should perhaps get a nobel peace prize for it). Destroying Iraq is genocide and a war crime. Or vice versa, depending on which side you're on.
The sides just flip flop, memory wipe past misdeeds, and then resume the perpetual partisan war. I think it works to assist them in staying in power, maintaining the always conflict. Oceania is always at war with Eastasia.
Will the US agression ever end? It is sickening.
The investigations are more successful so more leakers and whistleblowers get caught.
People think that because they are capable of pitching an anti-synthesis against a synthesis, they are intelligent - whereas nothing could be further from the truth. If you can't get out of the pro-vs-con mindset you are stuck in a trap designed to ensure you don't think beyond the curve, outside the event horizon of 'generally approved thought-process' society.
People need to be given uncomfortable positions to evaluate. Just maybe, its important to not discount the conspiracies and realise that in fact truth is stranger than fiction ..
I think the assumption that the wrongdoing was a conspiracy to get Trump elected gets far too much attention and is a secondary issue, but unlike the birther issue, there was quite a bit of funny business in general. The birther issue was just made up a priori.
The funny business, regardless of whether it benefited anyone, needs to be investigated. Once we understand what happened, then we can worry about whether it was an effort to swing the election or just a tactic for creating chaos.
It doesn't matter who's President.
It absolutely matters when something goes wrong outside our borders.
If, hypothetically speaking, a small NATO country on Russia's border devolves into chaos thanks to, say, a massive power grid failure combined with agitation from Russian nationalists, and Russia then intervenes to "stabilize" the situation, the temperament of the president and coherence of the White House as a whole would make a great deal of difference in how the crisis evolves.
Purely hypothetical, of course.