Following a visit to South Vietnam, Defense Secretary McNamara reports in a memorandum to President Lyndon B. Johnson that the South Vietnamese government of Nguyen Cao Ky "is surviving, but not acquiring wide support or generating actions."
He said that Viet Cong recruiting successes coupled with a continuing heavy infiltration of North Vietnamese forces indicated that "the enemy can be expected to enlarge his present strength of 110 battalion equivalents to more than 150 battalion equivalents by the end of 1966." McNamara said that U.S. policymakers faced two options: to seek a compromise settlement and keep further military commitments to a minimum, or to continue to press for a military solution, which would require substantial bombing of North Vietnam.
In conclusion, McNamara warned that there was no guarantee of U.S. military success and that there was a real possibility of a strategic stalemate, saying that "U.S. killed in action can be expected to reach 1,000 a month." In essence, McNamara cautioned Johnson that sending additional troops was not likely to prevent the stalemate. In the end, however, Johnson chose to seek a military solution. By 1969, there were more than 500,000 U.S. troops in Vietnam.