"Dereliction of Duty" is a book written by H.R. McMaster, a retired United States Army Lieutenant General, and published in 1997. The book examines the decision-making process of the Joint Chiefs of Staff during the Vietnam War and argues that their failure to provide independent military advice to the President and Secretary of Defense was a significant factor in the war's outcome. McMaster argues that the Joint Chiefs were overly deferential to political leaders and failed to provide critical military analysis that could have prevented the United States from becoming embroiled in a protracted and ultimately unsuccessful conflict. Drawing on extensive archival research, interviews, and personal experience, McMaster provides a detailed and compelling analysis of the strategic and operational failures of the US military leadership during the Vietnam War. "Dereliction of Duty" is a highly influential work that continues to shape debates about civil-military relations and the role of military advice in American foreign policy.