It was 1958, the era of Pom Poms and nuclear tests, when a candy mogul from Indiana decided to make conspiracy his postretirement hobby. Robert H.W. Welch brought together 11 of the most powerful businessmen in America (including Fred Koch, father of the famous Koch brothers) to cook up a plan for combating the secret cabal he believed was controlling the government. By the mid 1960s, the John Birch Society had tens of thousands of members. From its headquarters in Belmont, Massachusetts, the group popularized conspiracy theories about illuminati infiltration, mind-control chemicals in tap water, and a United Nations’ plan to establish a one-world government, eventually pushing so hard to the fringe that conservatives began to wince. The current iteration of the society is significantly diminished from its heyday in the ’60s, but Welch’s worldview has permeated American politics. So much of contemporary far-right thought can be traced back to the John Birch Society that one might say QAnon and the Koch network both crawled out of the same ideological soup. This March, Matthew Dallek, a professor and political historian at George Washington University, will discuss his new book on the society titled Birchers: How the John Birch Society Radicalized the American Right, at Politics and Prose. The talk starts at 7 p.m. on March 21 at Politics and Prose’s Connecticut  Avenue location. Free.