Historiography and tracking sources. It's actually a big field right now in terms of studying modern conservatism. Historians are examining dog whistle politics and really reinterpreting, shining light on how strains of the past have been repackaged to continue furthering an agenda... Let alone the addition of "new" issues.

So for example, Orientalists don't exactly exist like they used to, but to oversimplify for this, neo-conservatives adopted Bernard Lewis, and to a degree Bernard Lewis could be classified as a neo-conservative, to legitimize their desired dichotomy. But this desire to create a dichotomy between the West and Islam can be best seen in the discourse around jihad and whether Islam is autocratic. The easiest way to deal with "historians" who are being polemic or subjective to meet a political end is to not engage them politically, but help show their faults in sources. Generally these polemics utilize the same sources, same articles. Most of them cite sources that with a few clicks you find are associated with neo-conservatism or those who deny the Holocaust for political reasons.

What I'm getting at is most of us have to write for journals and make it out of our department before we even get to write a book. If you get published without having it torn to shreds by your fellow historian, I don't think you will even be considered. Classic example is Zinn's rise and fall. Zinn has left the historian's shelves and entered the shelves of public education. Soon Lies My Teacher Told Me will include a few of Zinn's own faults!

Our expert /u/commiespaceinvader has written at length about the way the historical profession combats Holocaust denial, and how others can do their bit. You can read their outstanding post here.

Irving is kind of a special category. Irving was dumb enough to sue someone to force the issue. Generally if someone's historical work isn't up to par other historians will write critical reviews or papers and books trying to make their case. It's a slow process but if you look at the work of someone like Eric Foner, he's gone back to the history of reconstruction and effectively gotten historians and the broader culture to look back at WEB Du Bois's Black Reconstruction. It's changed the historiography. Now I don't think there's a credible historian who really argues the States Rights case for the US Civil War.

With Irving, b/c he was such a special case you have Deborah Lipstadt writing on the libel trial with her book History on Trial. After the trial Richard Evans, who was Lipstadt's expert on historical matters, wrote a book called Lying About Hitler to expose some of the common lies and distortions that Holocaust deniers use. So, they're only partly writing about the history. They're writing about the tactics that people use to mislead others. The trial and most of scholarship has proven that Irving was purposefully deceiving his audience. It's rare that a case is so clean cut.

You can kind of watch the process starting now with Nancy MacLean's book Democracy In Chains. There are accusations that she took quotes out of context, her citations don't support her claims, or that her claims just aren't supported. Her subject is recent enough that people involved in many of the events described are pointing out discrepancies. There's been a series of critical reviews calling out the quality of the work. If you google her book and criticism there'll be no shortage. But this is usually the first step. People right critical reviews of history that they find dishonest. They'll also write papers or books explaining what they think the actual case is. In these cases either the work will stop being cited or will end up being cited as a cautionary example.

If you have time check out what happened with Charles Murray's The Bell Curve. It's not a historical text but the process is instructive. The book came out (This was done in a weird way that hurt the books credibility). There were a series of reviews criticizing and supporting the book. Then there was a cottage industry of books and papers offering refutations.