What's different now is the pervasiveness and precision of mass media. News used to be kind of restricted: a newspaper in the morning, maybe an hour of TV news at night. You might discuss it at the water cooler or family gatherings.

This changed in the 90s with the 24 hour news cycle, which shifted the news from a duty you performed as a citizen, to entertainment for hours a day. Then social media meant you could argue about it all day long -- again, for entertainment. People have always been susceptible to media manipulation, but they've never spent as much time willingly exposing themselves to it and reinforcing it on each other.

I don't believe the number of media sources is an issue. The truth is readily accessible. It's hard to be genuinely informed on a matter involving expertise, but that just leads to the conventional dumb votes. Now, people are seeking out misinformation, which is different from ordinary ignorance. It used to be hard to target people for actively disinforming them, but techniques for that have been improving for decades.

In the last 15 years, campaign spending doubled in real terms, advertising moved to new digital media which are more targeted and harder to regulate, and the Supreme Court gutted Congress’s ability to address these problems with legislation.