Following the reorganization of U.S. troops in early 1966, the capacity of second assistant division commander within 3rd Marine Division was terminated and Platt was appointed chief of staff, III Marine Amphibious Force under General Walt on March 15.
The political situation in South Vietnam was complicated by the fact, that commander of I Corps in Huế, lieutenant general Nguyễn Chánh Thi, oversaw I Corps with a great deal of autonomy and began directing agitation against the government in Saigon.
Prime Minister of South Vietnam, Nguyễn Cao Kỳ, ordered relieving of General Thi on March 11, 1966.

This act caused an immediate shock wave throughout I Corps area on the announcement of his removal, approximately 2,000 persons, including ARVN soldiers, marched through the streets of Da Nang and Huế in protest and a general strike was launched.
Marines tried to calm down the situation, but without success.
Platt took part in the negotiations with rebel ARVN officers and tried to persuade them to cease the rebellion.
During a visit to ARVN 1st Division headquarters in Huế, Platt accompanied Major General Huỳnh Văn Cao, who tried to persuade division commander, Brigadier General Pham Xuan Nhuan, to cooperate with Government forces.
Their attempt was not successful and Platt and his companions were attacked by angry crowd, which had broken into the division compound.
They hastily boarded the U.S. Army helicopter waiting for them and as the aircraft lifted off, an rebel ARVN lieutenant fired two pistol shots at it at point blank range.
Although not hitting any of the occupants, both rounds struck the helicopter.
After the second shot, the U.S. Army helicopter gunner fired a six-round burst killing the rebel ARVN lieutenant and wounding two other Vietnamese soldiers.
The rebel forces immediately made the dead lieutenant a "martyr" to their cause and accused the Americans of blatant interference in South Vietnamese internal affairs.
The unrest which was later known as the Buddhist Uprising lasted until June 8, 1966, when Saigon government forces regained control of Da Nang and Huế.

Platt remained in Vietnam until the beginning of December 1966, when he was succeeded by brigadier general Hugh M. Elwood and ordered back to the United States.
He received a third Legion of Merit with Combat "V" for his service as chief of staff, III MAF and also was decorated with Vietnam National Order of Vietnam, rank Knight and Vietnam Gallantry Cross with Palm by the Government of South Vietnam.
Following the reorganization of U.S. troops in early 1966, the capacity of second assistant division commander within 3rd Marine Division was terminated and Platt was appointed chief of staff, III Marine Amphibious Force under General Walt on March 15. The political situation in South Vietnam was complicated by the fact, that commander of I Corps in Huế, lieutenant general Nguyễn Chánh Thi, oversaw I Corps with a great deal of autonomy and began directing agitation against the government in Saigon. Prime Minister of South Vietnam, Nguyễn Cao Kỳ, ordered relieving of General Thi on March 11, 1966.
This act caused an immediate shock wave throughout I Corps area on the announcement of his removal, approximately 2,000 persons, including ARVN soldiers, marched through the streets of Da Nang and Huế in protest and a general strike was launched. Marines tried to calm down the situation, but without success. Platt took part in the negotiations with rebel ARVN officers and tried to persuade them to cease the rebellion. During a visit to ARVN 1st Division headquarters in Huế, Platt accompanied Major General Huỳnh Văn Cao, who tried to persuade division commander, Brigadier General Pham Xuan Nhuan, to cooperate with Government forces. Their attempt was not successful and Platt and his companions were attacked by angry crowd, which had broken into the division compound. They hastily boarded the U.S. Army helicopter waiting for them and as the aircraft lifted off, an rebel ARVN lieutenant fired two pistol shots at it at point blank range. Although not hitting any of the occupants, both rounds struck the helicopter. After the second shot, the U.S. Army helicopter gunner fired a six-round burst killing the rebel ARVN lieutenant and wounding two other Vietnamese soldiers. The rebel forces immediately made the dead lieutenant a "martyr" to their cause and accused the Americans of blatant interference in South Vietnamese internal affairs. The unrest which was later known as the Buddhist Uprising lasted until June 8, 1966, when Saigon government forces regained control of Da Nang and Huế.
Platt remained in Vietnam until the beginning of December 1966, when he was succeeded by brigadier general Hugh M. Elwood and ordered back to the United States. He received a third Legion of Merit with Combat "V" for his service as chief of staff, III MAF and also was decorated with Vietnam National Order of Vietnam, rank Knight and Vietnam Gallantry Cross with Palm by the Government of South Vietnam.
Jonas M. Platt