Jonah Goldberg's intent is not academic -- he even says as much in the beginning of the book -- but political. Rather than elucidating fascism he is arguing against a cultural meme that the right of the USA is fascist, and that the liberal left is anti-fascist, by going back into the history of fascism, finding progressive liberals who defended fascism as a good thing, and drawing parallels between the fascist program and progressive liberals today.
What this misses is Paxton's insight -- that fascism wins adherents by using the language of the left, that they are motivated by similar ills, but:
... the methods of intellectual history become much less helpful beyond the first stage in the fascist cycle. Every fascist movement that has rooted itself successfully as a major political contender, thereby approaching power, has betrayed its initial antibourgeois and anticapitalist programs. The processes to be examined in later stages include the breakdown of democratic regimes and the success of fascist movements in assembling new, borad catch-all parties that attract a mass following across classes and hence seem attractive allies to conservatives looking for ways to perpetuate their shaken rule. At laster stages, successful fascist parties also position themselves as the most effective barriers, by persuasin or by force, to an advancing Left and prove adept at the formation, maintenence and domination of political coalitions with conservatives. But these political successes come at the cost of the first ideological programs. Demonstrating their contempt for doctrine, successfully rooted fascist parties do not annul or amend their early programs. They simply ignore them, while acting in ways quite contrary to them. The conflicts of doctrine and practice set up by successful fascist movements on the road to power not only alienate many radical fascists of the first hour; they continue to confuse many historians who assume that analysing programs is a sufficient tool for classifying fascisms. The confusion has been compounded by the persistence of many early fascisms that failed to navigate the turn from the first to the second and third stages, and remained pure and radical, though marginal, as "national syndicalisms" — Paxton, p 14 -- 15
Goldberg's interest is not in understanding fascism. It's in flipping a cultural script within the United States -- one that is partially manufactured, since his characterization of the progressive left is largely based off of memes and cultural feelings -- so that the right is not fascist, but the left's
roots are, because fascism seeks to change society.
But the change of progressive politicals, the change of Marxists, the change of the Left differs markedly from the change sought by fascism. In addition, it is impossible to separate out the intellectual notions of fascism from the historical events of fascism. This is where we get to see the real impact of fascism. In particular it is noteworthy that fascists were not coherent. They were populists -- and so they would have to ally themselves with the working class at some point, just as they had to ally themselves with the conservative forces at another point. They wanted to fuse the classes into one structure, the state, and by that method overcome class divisions. This isn't even close to bread-and-butter progressive politics.
((EDIT: It's worth noting that Goldberg is a senior editor for the
National Review, -- given this position it makes sense that his aims are more political than academic, so seeking to learn about the nature of fascism from his book is a poor decision. He's talking american politics more than he's talking about fascism in that book))