A taste for gunmen on the grassy knoll

What comes clear in “Voodoo Histories’’ is how much conspiracy theories are really confirmation theories, political or social myths that confirm anxieties. As Aaronovitch argues, “There is a more than plausible argument to be made that, very often conspiracy theories take root among the casualties of political, social and economic change.” This is particularly true in American political history, where our native populism has created factions eager to claim responsibility for successes, but even more eager to lay blame for failures at the feet of a rotating collection of scapegoats. Variously, New Deal liberals, African Americans, big business, Republicans, and most consistently, immigrants have been fitted for the black hat of conspiracy.