I don't think it will ever entirely be a thing of the past, because humans are inventive and humans who wish to exercise control over their fellows will continually invent new means to do so, but I think we have a lot of room for improvement in the area of making that as difficult as possible.

One example is in media segmentation. I think one of the things that made Trump able to succeed is the extent to which he and his allies controlled the media diets of his constituency. People outside their control tend to think of American Republicans as ignorant, hateful people beyond reason. That's not untrue, but it really undersells the massive amount of control Republican leaders have over the lens their constituents have on the world. Outside the see the Fox News histrionics about cities being overrun by drugs, and gangs, and drug-gangs, and we turn to one another and laugh at the idea that anyone could believe such an obviously not true thing. For those deep inside the bubble, they believe it because they never see any contradiction to that narrative, ever. They don't go into cities that often, and when they do they have been conditioned to be afraid of phantom criminals. They watch the news their parents watched, listen to the AM radio, and read websites they learned about in the church they grew up in, from people they have been taught to trust. They aren't stupid, at least not all of them. It's very weird, and very sad, to see up close how decades of uncontested conservative propaganda blasting can warp the fundamental assumptions a person has about the world.

Anyway I think the internet is a pretty handy medium for making inroads into those bubbles. It sounds pollyanna-ish, I think, given the current sickly state of the Internet, but one of the lessons I hope the world pulls from the American trainwreck is one on how to better identify and puncture media bubbles. That shit will kill us if we let it.

The roots are older than any of us. For the US, the line "We hold these truths to be self-evident, that all men are created equal" has been a hypocritical fiction since the day Jefferson put pen to paper. When I was a kid I was taught that it was more of an ideal that we were slowly but inexorably marching toward, and I just don't think "maybe, someday" is an acceptable timeframe for something as critical as equality under law.

I think Jeffs was on the right track, and that holding some variant of "all persons are equal under law" as axiomatic is necessary for democratic government, but in 250 years we have never satisfactorily held ourselves to the standard we claim to hold, and the consequences of that hypocrisy have waxed and waned over the decades as the Rupert Murdochs of the world have sought to exploit it to their own ends, but it's never not been present in some fashion.

To extend the cancer metaphor, I don't know that a cure can be trusted to stick, even if we can get the current wave into remission. Countries of a certain age need routine screenings and effective early-stage interventions, and the US has done neither consistently. I don't really know what working versions of those would look like. I think the origins of fascism have a mutagenic quality that make any one treatment a mere stop-gap until some selfish one finds a way to circumvent it, so maybe it's more a game of constant vigilance and treating outbreaks as they occur, decisively, than coming up with one all-encompassing solution.