Undersecretary of State George Ball submits a memo to President Lyndon B. Johnson titled "A Compromise Solution for South Vietnam." It began bluntly: "The South Vietnamese are losing the war to the Viet Cong. No one can assure you that we can beat the Viet Cong, or even force them to the conference table on our terms, no matter how many hundred thousand white, foreign (U.S.) troops we deploy." Ball advised that the United States not commit any more troops, restrict the combat role of those already in place, and seek to negotiate a way out of the war.
As Ball was submitting his memo, the U.S. air base at Da Nang came under attack by the Viet Cong for the first time. An enemy demolition team infiltrated the airfield and destroyed three planes and damaged three others. One U.S. airman was killed and three U.S. Marines were wounded.
The attack on Da Nang, the increased aggressiveness of the Viet Cong, and the weakness of the Saigon regime convinced Johnson that he had to do something to stop the communists or they would soon take over South Vietnam. While Ball recommended a negotiated settlement, Secretary of Defense Robert McNamara urged the president to "expand promptly and substantially" the U.S. military presence in South Vietnam. Johnson, not wanting to lose South Vietnam to the communists, ultimately accepted McNamara's recommendation. On July 22, he authorized a total of 44 U.S. battalions for commitment in South Vietnam, a decision that led to a massive escalation of the war. There were less than ten U.S. Army and Marine battalions in South Vietnam at this time. Eventually there would be more than 540,000 U.S. troops in South Vietnam.