Book excerpt: Roger Roffman first discovered marijuana while serving as a US Army officer in Vietnam. From these seemingly innocuous beginnings, Roffman has been fascinated by marijuana, as a researcher, scholar, therapist, activist, and user. Ever since America’s youth first marched in opposition to the war in Vietnam, pot’s popularity has periodically ebbed and surged. Calls for greater, fewer, or no marijuana penalties also have swung on their own pendulum.From lobbying in Washington, to talking to doctors and nurses in oncology wards, and watching his brother struggle with addiction, Roffman has experienced the layered and complex relationship Americans have with marijuana first-hand. With one foot on each side of the fence, at times feeling at odds with both camps, Roffman is on a quest to challenge those who insist we think of marijuana as a weapon of mass destruction, as well as those who would have us see it as a harmless source of pleasure and relief.