This volume rests on a simple proposition: The legal arguments against military intervention in Vietnam were wrongly rejected by the US government and, until these are reconsidered and reversed, failure abroad and deterioration at home are the likely results.

It may seem, with the passage of more than fifty years since the American military engagement in Vietnam became a serious commitment of national policy, that the legal controversy that accompanied the involvement should be forgotten, and that the most reasonable recommendation would be to move on. The world has changed drastically in this past half-century, as has – especially – the context in which force is used, creating a drastically different relationship between international law and recourse to force beyond the borders of a sovereign state.

Actually, the passage of time and the preoccupation with present security challenges have led to an unfortunate neglect of the Vietnam precedent, which retains an extraordinary relevance, especially for the development of American thought and practice relative to military intervention in foreign societies. As this collection of writings attempts to show, unlike more recent legally dubious interventions, especially associated with the attack on Iraq in 2003, there has been no high-profile government attempt to provide a convincing legal rationale for its recourse to force.

Until Vietnam, with some important exceptions relating to covert intervention as in Iran (1953) and Guatemala (1954), the United States was associated with the promotion of the rule of law in international political life and an attitude of respect toward the constraints on the use of force set forth, largely at the urging of Washington, in the Charter of the United Nations. Constructing a global legal order was a vital ingredient of its leadership role assumed at the end of World War II, and reinforced by the backing of the UN in the Korean War and the stand against recourse to war and acquisition of territory through force by its European allies and Israel in the 1956 Suez War.