Johnstone takes a potentially intriguing premise--an organized uprising of US militia organizations--and squanders it.
Perhaps I expected too much; Johnstone's other novels get good marks from other readers here at amazon. But the writing seemed poor and cliche-ridden. Gross generalizations and observations by the narrator drove most of the plot. It seemed that the characters were there to act out the inevitable. Like actors in a 1950's propaganda film, their motivations were not their own.
Many of the historical points he makes are false or inaccurate, which makes it hard to suspend your disbelief for the rest of the story. For example, one of the heroes describes the causes of homelessness: "Of course, seventy-five percent of them would still be...clean and dry and fed and medicated if the goddamned liberals hadn't opened all the doors to mental institutions and turned them loose to fend for themselves." Hmm, Ronald Reagan a liberal? First I've heard of it.
I'm politically moderate, so the unabashed Limbaugh-ism didn't scare me. However much of it was more mean-sprited than necessary, and again often inaccurate. A college professor is described as "An acid-tongued, vicious, man-hating dyke." It's all we ever see of her, so who knows where this came from? A lot of it is just out-of-touch with reality. At one point, Democratic senators denounce each other as Marxists and socialists.
Epithets of all kinds flow freely, based on race, sexual orientation, politics, you name it. It all comes from the characters' mouths, so it's possible that Johnstone himself isn't propounding all these views. However, there's little balance--the conservatives tend to dish it out and the liberals take it. And much of the verbal abuse is flung by the heroes of the story, the ones we're supposed to identify with.
In sum, "Breakdown" is an interesting premise turned into a cartoonish arch-conservative farce.