Henry A. Kissinger’s decision to authorize the secret carpet bombing of Cambodia, his efforts to negotiate the American exit from the Vietnam War and his role in the U.S. rapprochement with China have rippled through Southeast Asia in the decades since.

Mr. Kissinger, who died on Wednesday, shared the 1973 Nobel Peace Prize for negotiating the peace accords that ended American involvement in the Vietnam War. But some critics accused him of needlessly prolonging the war when a framework for peace had been available years earlier.

The fighting between North Vietnam and U.S.-backed South Vietnam did not end until the North’s victory in 1975. Some observers have said that was the inevitable result of a cynical American policy intended to create space — “a decent interval,” as Mr. Kissinger put it — between the American withdrawal from the country in 1973 and the fall of Saigon two years later.

The bombing of Cambodia in 1969 and 1970, which Mr. Kissinger authorized in the hope that it would root out pro-Communist Vietcong forces operating from bases across Vietnam’s western border, also fueled years of debate about whether the United States had violated international law by expanding the conflict into an ostensibly neutral nation.