Ralph Waldo Emerson once remarked, “Books are the best of things, well used; abused, among the worst.” Whether and how books may be abused is the question Ann Larabee tackles in The Wrong Hands: Popular Weapons Manuals and Their Historic Challenges to a Democratic Society. Larabee supplies a well-documented account of the dissemination of destructive knowledge. Dangerous information—how to make dynamite, how to lay an ambush, how to produce poison—migrates in two dimensions. The first dimension is from the elites down to the masses: applied chemistry treatises and army survival manuals are shamelessly copied, repackaged, and distributed by radical pamphleteers, fringe publication houses such as Paladin Press, and, in more recent years, by blogs, chat groups, and peer-to-peer file-sharing software. The second dimension is across the political spectrum. Anticapital anarchists publish tracts on the best way to build a bomb, sometimes seasoning the bland technical details with inflammatory political screeds. Anticommunist reactionaries take their instructions, strip out the Marxist cant, and put in their own, right-wing bluster; they, in turn, are plagiarized by environmental groups and Islamic radicals, who add their own political flavor. The overwhelming sense from Larabee is that the technical details—some- times accurate, sometimes n