The next time a TSA goon manhandles your junk, thank a writer named William Powell. His Anarchist Cookbook, which turns 40 this year, laid out how to build nitric acid explosives out of everyday objects, cook homemade nitroglycerin, and sabotage communications systems from the comfort of your home, all in concise, approachable language. It launched the era of the everyman bombmaker—and the notion that no one’s above suspicion.