The Johnson administration and its handling of the war in Vietnam comes under attack from several quarters. A group of 22 eminent U.S. scientists, including seven Nobel laureates, urged the President to halt the use of antipersonnel and anti-crop chemical weapons in Vietnam. In Congress, House Republicans issued a "White Paper" that warned that the United States was becoming "a full-fledged combatant" in a war that was becoming "bigger than the Korean War." The paper urged the President to end the war "more speedily and at a smaller cost, while safeguarding the independence and freedom of South Vietnam."
Johnson's handling of the war was also questioned in the United Nations, where Secretary General U Thant proposed a three-point plan for peace in Vietnam, which included cessation of U.S. bombing of the North; de-escalation of the ground war in South Vietnam; and inclusion of the National Liberation Front in the Paris peace talks. In Rome, Pope Paul VI appealed to world leaders in a papal encyclical to end the Vietnam War. Despite such calls, the United States launched extensive bombing raids by B-52s that lasted for four days against a mixture of targets in the DMZ, including infiltration trails, troop concentrations, supply areas, and base camps.