Excuse.
This is nothing to do whether owned sovereignty.
of course you did not sovereignty, the sovereignty of these two islands belong to China.
Prime Minister Phạm Văn Đồng confirmed China's sovereignty through official channels . Also means that do not recognize other countries own the sovereignty of these two islands .
these two island South Vietnamese not own sovereignty
So sovereignty can not be used to make excuses
Note that, South Vietnam had soldiers there to protect our sovereign, here is history.
26/10/1954: Taking advantage of the Vietnamese forces preoccupied in the battle against French colonialism, China sends fleets to occupy Paracel and Spratly archipelagos illegally.
4/1950: China withdraws all of its forces from the Spratly, then the Paracel archipelagos.
1954: Vietnam divided into North and South at the 17th parallel as determined at the Geneva Conference. The North becomes the Democratic Republic of Vietnam, a communist state supported by China and the USSR. The strict communist ideology began to prevail at the 2nd congress of the Vietnamese labor party in 1951. In 1955, Ngo Dinh Diem becomes president of the Republic of South Vietnam with backing from the West.
1956: China launches naval units to the islands.
4/9/1958: China declares that the Paracel and Spratly archipelagos are within its sea territories even though at that time, South Vietnam had already claimed control over these islands.
19/1/1974: China invades the Paracels and a battle takes place between Chinese and South Vietnamese forces. One warship was sunk, while two others were heavily damaged on the Chinese side. Vietnam also lost a warship with two others damaged, along with the lives of 70 fighters.
1975: Fall of South Vietnam to Communist North.
1976: Reunification officially proclaimed. The country is called the Socialist Republic of Vietnam.
17/2/1979: China invades Vietnam as a retaliatory act for putting an end to the murderous China supported Pol Pot regime in Cambodia. China was repelled after a month of fighting.
30/7/1979: China releases documents that claim that Vietnam supposedly “admmited” Chinese sovereignty over the islands to the protest of Hanoi on 7/8/1979.
1980: China releases the White Papers with various ill-founded reasons for while the archipelagos belonged to China after Vietnam released its White Papers in 1979.
1/6/1984: China sets up administrative area of Hainan which includes Paracel and Spratly archipelagos.
10/11/1987: Chinese forces make their way onto the Louisa Reef in the Spratly islands. China conducted naval patrols and established a permanent base on the Spratly islands.
1-4/1988: Chinese forces take over more features. China and Vietnam ships clashed over Johnson Reef. Chinese forces prevailed and retained control of the area.
