Olmsted is a smart historian, and her book is full of smart history, but her thesis is dead wrong and makes things worse. [Thread about distinguishing conspiracy theory from justified strong skepticism]
Conspiracy theorists are different in kind, not degree, from critical thinkers trying to unmake government plots to deceive their citizens in at least 2 key ways.
1st, conspiracy theorists don't blame government for government conspiracies. Ultimate actors are Illuminati, Jews, etc. This is the first thing that defines them as conspiracy theorists.
2nd, conspiracy theorists have opposite criteria for evaluating testimony from the rest of us. They valorize stimatized knowledge because it is stigmatized. This is the second thing that defines them.
Critical doubters share canons of argument with government supporters, both in general and in detail. We usually both mostly agree cui bono and that evidence at hand has gaps.
The difference is that doubters insist on an elevated burden of proof before acting. This is rationally based on a past record of deception in similar contexts by the same actors. We also think deadly force should not be used precipitously because costs.
Government supporters believe burden of proof should be lower and need for speed is higher. These mutually reinforce.
In every such heated argument there will be fierce confirmation bias on both sides. That is often called conspiracy thinking, but it is not. It is an inescapable stage in rational inquiry. (Conspiracist charges also used as a rhetorical weapon, to delegitimate opponents.)
Olmsted's scheme is designed to obscure this. She thinks studying proven government conspiracies offers a key to understanding conspiracy thinking. it is the opposite. It fatally confuses the issues.
It is true that conspiracy thinking finds nourishment in past conspiracies and in pentagon "scenario thinking." It also finds nourishment in nothing at all (viz. chemtrails). The content of conspiracy theory is not the key to it. That's what makes it what it is.
Conspiracy thinking is a form of religion. It's manichean, apocalyptic and millenarian. The world is divided into two sides, fighting to the death, and you can read the signs everywhere if you know how. And you can engage in theological debate.
This is the head and shoulders the best book on its dynamics and modern developments from 1970 through 2010: amzn.to/2Jy4dXI
Barkun's book is not in Olmsted's bibliography, and that's not an accident. The American historical tradition has been running in the wrong rut on this since Hofstaedter. Smart people turn up smart things, but muddle the main question irreparably.
Partially that's because if there are materials fit for a historian, the task is too easy to matter. The real problem arises when materials are still hidden. How much doubt is justified then? How much guessing?
Because of that, this is job for investigative journalists, not historians. And careers of Robert Parry & Seymour Hersch show the danger of going where things can't be proven and TPTB are against you.
