I think that it's fair to say that both the campaign and presidency of Donald Trump are unlike anything that we have ever seen before. Quite apart from the fact that he is the first person in the Oval Office to have never held any other public office before (if you don't include Dwight Eisenhower¹), he's come to the job with seemingly no intention of trying to bind the wounds of the country nor does he seem that interested in talking across the aisle. What we have is someone marching to the beat of a drum which is so different from anything and anyone ever gone before that people are still having a hard time at comprehending what in blue blazes is going on.
There are several things which aren't new at all though. This era of pure vitriol could have easily sat within the time period of Adams and Jefferson, or Hamilton and Burr, or Andrew Jackson and everyone else in the world. In the grand scheme of history Trump's presidency is not immensely different from others; you might even say that conflict is almost a default setting of the US government system. Trump's use of Twitter isn't that remarkable either. This just happens to be the communication vehicle of the day.
Going backwards in time, Ronald Reagan was the first to properly master the use of television and a means of saying what he wanted to the people. Having previously been an actor and a television host before becoming President, he knew the value of cultivating an image and using the medium to speak directly to the public.
Going back even further, Franklin D Roosevelt used the then current technology of radio to speak right into people's living rooms. His "fireside chats" were state of the art at the time. It's also kind of amusing to note that he made use of his voice as an instrument for the medium and unlike presidents before him, he didn't need to resort to shouting in an effort to make himself heard.
Immediately before him, Herbert Hoover appeared in what would now be disparagingly called propaganda films but given that the world hadn't really seen moving pictures before the turn of the century, to suddenly seeing pictures with sound and vision² by the end of the 1920s, then the use of cinema as a medium is very much embracing the future.
Before vision and sound could be recorded, the only way that anyone found out about what the President had said was via print media or listening in person. For the latter of the two and indeed for most of history, immediately after someone said something, it was lost into the ether forever. For the former, because we tend to absorb printed media so much more slowly than anything else, it tends to have a greater impact. This is obvious when most people say that they enjoyed the book more than the movie in almost every case³. When you think about the most famous speech in American political history, Abraham Lincoln's Gettysburg Address, probably only a few select people actually heard it because it was recorded that he had a notoriously squeaky voice and that it was only 272 words long: the power of that speech lies in the fact that it had been released to the press and appeared in newspapers.
Going back to the founding of the United States and we see that Adams and Jefferson conducted a feud via print media which ironically in today's age of shamelessness would have been seen as scandalous and probably would have landed them both in court on cross-counter defamation charges.
Going back to President Trump, probably a great reason why he was elected in the first place was because he was able to bypass the gatekeepers of traditional television and print media and speak directly to the public. People might say that Obama was the first social media President but Trump's use of Twitter in particular is just part of a grand tradition of presidents using whatever the latest mode of media happened to be. The fact that you now have media companies hanging off every single tweet is indicative of both the 24 hour news cycle and the impatience of the general public. His use of Twitter though isn't exactly remarkable though.
¹Ike didn't even want the job. That made Ike the kind of fellow they like. I like Ike.
² People were just waiting for the gift of sound and vision.
³There are exceptions. I for instance preferred The Lord Of The Rings as movies because I find the prose of Tolkien to be hideously tedious.