He is saying that those that lose out in the political divide are likely to rebel and if strength is on their side prevail, And that the death of the Republican Party in California is likely to be followed by the rest of the country. He puts the timeframe of 15 years on this development but I don’t think we have 15 years.

https://medium.com/s/state-of-the-future/the-great-lesson-of-california-in-americas-new-civil-war-e52e2861f30

The Great Lesson of California in America’s New Civil War

Why there’s no bipartisan way forward at this juncture in our history — one side must win