If you’re new to thinking about US fascists and far-right, including their alliances with police as well as their opposition to (aspects of) the US state, I encourage you to check out Three Way Fight blog: https://threewayfight.blogspot.com/?m=1
One of the people behind the blog, Matthew Lyons, has written extensively on far-right movements that have been mobilizing for today’s assault. See his book Insurgent Supremacists, published by @PMPressOrg https://matthewnlyons.net/books/insurgent-supremacists/
A number of journalists have been covering fascist & far-right movements for years. Among the best: @chick_in_kiev @shane_burley1 @DavidNeiwert
As others have stated, @kathleen_belew’s book Being the War Home is an essential guide to understanding the origins of today’s violence: https://www.kathleenbelew.com/bringthewarhome
And @joelowndes has been tracking right-wing movements for years. See, among others, his book with Daniel Martinez HoSang: https://www.upress.umn.edu/book-division/books/producers-parasites-patriots
I know I left out a lot of sharp thinkers and organizers on the subject but only have time for one more addition right now: @MsKellyMHayes and her @truthout podcast and articles, Movement Memos https://truthout.org/series/movement-memos/
“You fight [fascists] by writing letters & making phone calls so you don’t have to fight them with fists. You fight them with fists so you don’t have to fight them with knives. You fight them with knives so you don’t have to fight them with guns...” quoted in @Mark__Bray, ANTIFA