The second unilateral pause in the bombing of North Vietnam occurs. It lasts for 37 days while the U.S. attempts to pressure North Vietnam into a negotiated peace. However, the North Vietnamese denounce the bombing halt as a "trick" and continue Viet Cong terrorist activities in the South.

U.S. troop levels in Vietnam reached 184,300. An estimated 90,000 South Vietnamese soldiers deserted in 1965, while an estimated 35,000 soldiers from North Vietnam infiltrated the South via the Ho Chi Minh trail. Up to 50 percent of the countryside in South Vietnam is now under some degree of Viet Cong control.

General William Westmoreland is chosen as Time Magazine's 1965's 'Man of the Year.'

During his State of the Union address before Congress, President Johnson comments that the war in Vietnam is unlike America's previous wars, "Yet, finally, war is always the same. It is young men dying in the fullness of their promise. It is trying to kill a man that you do not even know well enough to hate...therefore, to know war is to know that there is still madness in this world."

1st Cavalry Division (Airmobile) begins Operation Masher on the Bong Son Plains, the first large search and destroy operation of the war. President Johnson orders the name of the 42-day operation changed to "White Wing" to avoid adverse U.S. public opinion. The operation lasts until 6 March 66.

Citing Hanoi's failure to respond to his peace overtures during the 37 day bombing pause, President Johnson announces bombing of North Vietnam will resume.

Senator Robert F. Kennedy criticizes President Johnson's decision to resume the bombing, stating that the U.S. may be headed "on a road from which there is no turning back, a road that leads to catastrophe for all mankind." His comments infuriate the President.

The largely antiwar Senate Foreign Relations Committee, chaired by Sen. J. William Fulbright, holds televised hearings examining America's policy in Vietnam.

Newspaper columnist Walter Lippmann lambastes President Johnson's strategy in Vietnam.

President Johnson and South Vietnam's Prime Minister Nguyen Cao Ky meet in Honolulu.

Sen. Wayne Morse moves to repeal the Gulf of Tonkin Resolution, but fails in the U.S. Senate by a vote of 92 to 5.

The 1st Cav's Operation Masher (White Wing) ends with 1,342 confirmed enemy dead. U.S. losses are 228 KIA and 788 WIA.

The U.S. reveals that 20,000 acres of food crops have been destroyed in suspected Viet Cong villages. The admission generates harsh criticism from the American academic community.

South Vietnamese Buddhists begin a campaign to oust Prime Minister Ky following his dismissal of a top Buddhist general. This marks the beginning of extreme unrest in Saigon, Danang and Hue as political squabbling spills out into the streets and interferes with U.S. military operations.

Anti-war protests are held in New York, Washington, Chicago, Philadelphia, Boston and San Francisco.

The U.S. uses B-52 bombers for the first time against North Vietnam. Each B-52 carried up to 100 bombs at an altitude of about six miles. Target selections, closely supervised by the White House, fall into six target categories; power facilities, war support facilities, transportation lines, military complexes, fuel storage, and air defense installations.

Viet Cong attack Tan Son Nhut airport in Saigon causing 140 casualties while destroying 12 U.S. helicopters and nine aircraft.

Secretary of Defense McNamara privately reports the North Vietnamese are infiltrating 4500 men per month into the South

Political unrest intensifies as South Vietnamese troops loyal to Prime Minister Ky overrun renegade South Vietnamese Buddhist troops in Danang. Ky's troops then move on to Hue to oust renegades there. Ky's actions result in a new series of immolations by Buddhist monks and nuns as an act of protest against his Saigon regime and its American backers. Buddhist leader Tri Quang blames President Johnson personally for the situation. Johnson responds by labeling the immolations as "tragic and unnecessary."

6,400 teachers and professors sign a three-page anti-war advertisement in the New York Times.

Political unrest in South Vietnam abates following the crackdown on Buddhist rebels by Prime Minister Ky, including the arrest of Buddhist leader Tri Quang. Ky now appeals for calm.

Citing increased infiltration of Communist guerrillas from North Vietnam into the South, the U.S. bombs oil depots around Hanoi and Haiphong, ending a self-imposed moratorium. The U.S. avoids targeting Hanoi itself over concerns for the reactions of North Vietnam's military allies, China and the Soviet Union. This concern also prevents any U.S. ground invasion of North Vietnam, despite such recommendations by a few military planners in Washington.