This volume covers the core period of US involvement in Vietnam, from July 1965, when the decision was made to send large-scale US forces, to the beginning of 1968, just before the Tet offensive and the decision to seek a negotiated settlement. Using a wide variety of archival sources and interviews, the book examines in detail the decisions of the president and Congress, and the growth of public and congressional opposition to the war. Differences between US military leaders on how the war should be fought are also included, as well as military planning and operations. Among many other important subjects, the financial efforts of the war and of raising taxes are considered, as well as the impact of a tax increase on congressional and public support for the war. Another major interest is the effort by Congress to influence the conduct of the war and to place various controls on US goals and operations.