God forbid that our readers should think that I think my relatives engage in the "contemplation of African-American history" before worrying whether some political development is good or bad for the Jews! Nor did I mean to imply that the Jews in Roth's novel are race-conscious, though it's not anachronistic to imagine that their counterparts in real life could have been. (The novelist Jonathan Rosen, who used to edit the Jewish Forward, just called to tell me about the first letter he ever got from Alfred Kazin. The great critic wrote to ask Jonathan to look up a headline Kazin was certain he had once seen in the Forward: "Pogrom in Pennsylvania." The article described a lynching. According to Kazin, there was also a cartoon of a black man hanging from the Statue of Liberty. Rosen never actually looked it up, but that's another story.)
I do attribute a certain amount of such awareness to Roth, though. Roth, who knows his way around American history, has palpably thought a great deal about the violence that has been done to blacks in this country. (See The Human Stain.) He has also thought a lot about the violence they have unleashed in return—see his many passages lamenting the devastation of Newark in the riots of the 1960s. Indeed, Roth's great subject in his so-called American trilogy (American Pastoral, I Married a Communist, and The Human Stain), as well as in The Plot Against America, is American violence in all its permutations, for which he came up with a wonderful phrase: the "indigenous American berserk."
Roth's indigenous berserk can attack from right or left. In the form of Weather Underground-style terrorism, it kills four innocent bystanders and ravages Swede Levov's family in American Pastoral; as McCarthyism, it takes down Ira Ringold in I Married a Communist; as first racism, then its mirror opposite, lunatic political correctness, it ruins Coleman Silk in The Human Stain; and as America First-ism in The Plot Against America, it reduces Alvin and Sheldon to stumps and nearly drives Herman Roth mad. The phrase itself sums up that Jewish terror of the outside world you identified in your first post. It suggests that American violence is not only native to Americans but intrinsic to them; that it lurks just beneath the surface and can be set off at any time; that it partakes of the madness particular to mobs; and that you ignore it at your peril.
But in none of the novels listed above does the indigenous American berserk affect only Jews. It always affects the entire nation, even if the nation doesn't understand how at the time. It is seen through the eyes and processed through the political sensibilities of individual Jews, but Roth is identifying a disease he calls in American Pastoral "the plague of America": the destructive and annihilating stupidity that comes over nations when they succumb to the psychology of the mob. So, while I agree with everything you say about Roth and his provincialism, I definitely think that insofar as his novels contain within them political essays (and they do, and why shouldn't they?), their analysis reaches beyond the particular situation of Jews. What he does in these four novels is reach deep within his knowledge of that Faulknerian Jewish world, create characters with all the ferocious specificity necessary to bring them to life, then throw those characters into the roaring headwaters of history and watch them drown or swim.
As we wrap this up I want to add one note in defense of The Plot Against America, lest people think I didn't like it. (I said it wasn't one of his greatest, not that I didn't like it. Roth could write a biochemistry textbook and I'd like it.) One of the best things about the book is its astonishing inventiveness. I've already praised its most magnificent invention, the OAA. But one of the biggest challenges of writing counterfactual history is getting the reader to go along as you derail the past from the known course of events. How was Roth going to get Lindbergh elected, given Roosevelt's enormous popularity? Why, his flyover campaign—he flew The Spirit of St. Louis from town to town, repeating his pioneering flight across America, attracting crowds and press and campaigning wherever he landed—which is a perfect way of commenting upon and exploiting exactly what was happening in America at the time: the simultaneous rise of technology, mass media, and mass culture. As a result, we have no difficulty imagining the cult worship of an aviator sweeping the nation and upsetting the establishmentarian political order.
There's more, but I've run out of room, and I fear our readers will run out of patience. We'll just have to take it offline.