Which 1971 book by William Powell was banned in many countries for instructions on explosives?

The 1971 book by William Powell banned in many countries for instructions on explosives was The Anarchist Cookbook.

Powell wrote the book during the Vietnam War era, when he was angry about U.S. military intervention and the political establishment. Published by Lyle Stuart in 1971, it combined political rhetoric with instructions involving explosives, weapons, drug production, and telephone phreaking. Its title suggested revolutionary purpose, although Powell later rejected the work and sought to have it removed from circulation.

The book’s accuracy is uneven. Much of the material was described as crude or unreliable, but an FBI review concluded that its explosives chapter appeared accurate in most respects. That combination of notoriety and practical danger made the book a recurring concern for law-enforcement agencies.

Its legal status varies by country. Australia refused classification in 1985 and again classified it as refused in 2016. In the United Kingdom, possessing it without reasonable excuse can support prosecution under terrorism legislation when the information is considered useful for preparing an act of terrorism. It has also faced restrictions or prior bans elsewhere, although it remains legally available in the United States.