President Johnson had already appointed General William C. Westmoreland to succeed General Harkins as Commander of MACV in June 1964. Under Westmoreland, the expansion of American troop strength in South Vietnam took place. American forces rose from 16,000 during 1964 to more than 553,000 by 1969. With the U.S. decision to escalate its involvement it had created the Many Flags program to legitimize intervention and ANZUS Pact allies Australia and New Zealand agreed to contribute troops and matériel to the conflict. They were joined by the Republic of Korea, Thailand, and the Philippines. The U.S. paid for (through aid dollars) and logistically supplied all of the allied forces.