I wonder if its possible for America to fix this horrible "if you aren't with us, you are against us" mentality. There seems to be no concept of a middle ground, no grey. Everything is either black or white. How did it end up like this?
What makes you think it wasn't always like this? If you were to go back in time any number of years up to, say, the administration of John Adams, you'd find that the popular political climate was equally nasty if not worse. Look up some contemporaneous quotes from the newspapers of past eras and you'd find stuff that made the Wall Street Journal editorial page look like a haven of reasonable moderation. Anti-immigrant hysteria used to be far worse, back when it was still directed at what we would now think of as "white people". Dallas, TX circa 1963 was like one giant rally of the John Birch Society. Posers like Rick Perry may mutter darkly about secession over Obamacare, but back in the 1860s the nutters really did secede, leading to a war that killed hundreds of thousands. There are just countless examples of extremist rhetoric and polarization.
What has genuinely changed is the pace at which information (and disinformation) is propagated, and the 24-hour news cycle, where every gaffe or poorly formed sentence is beaten into the ground as an example of the other side's perfidy. And the number of news sources has multiplied, so instead of having just a handful of newspapers (and the occasional pamphlet) run by oligarchs, we have a variety of modern media, especially the Internet. Which means that we all have instant access to the same cesspool of slander and lies, whereas in the 19th century - or even the mid-20th - someone living in a small midwestern town would be relatively ignorant and isolated, and might be fooled into believing that their local newspaper was representative of the national "discussion". (Actually, this describes most of us who grew up in the pre-Internet era, at least those of us who are too young to have witnessed the 1960s or the Nixon administration.)