Operation Trikora

When the rest of the Dutch East Indies became fully independent as Indonesia in December 1949, the Dutch retained sovereignty over the western part of the island of New Guinea and took steps to prepare it for independence as a separate country. The Dutch and West Papuan leaders argued that the territory did not belong to Indonesia because the West Papuans were ethnically and geographically separated from Indonesians, had always been administrated separately, and that the West Papuans did not want to be under Indonesian control.[2] From its independence in 1949 until 1961, Indonesia attempted to gain control of Western New Guinea through the United Nations without success. Since the Indonesian National Revolution, Indonesian nationalists had regarded Western New Guinea as an intrinsic part of the Indonesian state.[3] They also contended that Western New Guinea (Irian Barat) belonged to Indonesia and was being illegally occupied by the Dutch.[4][5]

Since 1954, Indonesia had sporadically launched military raids into Western New Guinea. Following the failure of negotiations at the United Nations, the president of Indonesia, Sukarno, escalated pressure on the Netherlands by nationalising Dutch-owned businesses and estates and repatriating Dutch nationals. These actions increased tensions between Indonesia and the Netherlands led to a sharp reduction in trade between the two countries. Following a sustained period of harassment of Dutch diplomats in Indonesia, Indonesia formally severed ties with the Netherlands in August 1960. Indonesia also increased its military pressure on Dutch New Guinea by purchasing weapons from the Soviet Union and the Eastern Bloc. Over the following years, the Sukarno government would become dependent on Soviet military support.[6]

On 19 December 1961, Sukarno decreed the establishment of the People's Triple Command or Tri Komando Rakyat (Trikora) in order to annex what Indonesia called West Irian by 1 January 1963. Trikora's operational command was to be called the Mandala Command for the Liberation of West Irian (Komando Mandala Pembebasan Irian Barat) with Major-General Suharto (the future President of Indonesia) serving as its commander. In preparation for the planned invasion, the Mandala command began making land, air, and sea incursions into West Irian.[4][7] As a result, Indonesia began a policy of confronting the Dutch over control of Western New Guinea.[6] Sukarno also embarked on a policy of "progressive mobilization" to prepare the nation to carry out his commands.[8]

While the United States, the United Kingdom and Australia sided with the Netherlands' claims to Western New Guinea and were opposed to Indonesian expansionism, they were unwilling to commit military support to the Dutch. The Netherlands was unable to find sufficient international support for its New Guinea policy. By contrast, Sukarno was able to muster the support of the Soviet Union and its Warsaw Pact allies, and the Non-Aligned Movement. In response to Indonesian claims, the Netherlands to sped up the process of implementing West Papuan self-rule from 1959 onward. These measures included the establishment of a legislative New Guinea Council in 1960, establishing hospitals, completion of a shipyard in Manokwari, development of agricultural research sites and plantations; and the creation of the Papuan Volunteer Corps to defend the territory.[9][10]

The disputed territory of West New Guinea

In 1962, Indonesian incursions into the territory in the form of paratroop drops and the naval landings of guerrillas were used to step up Indonesian Foreign Minister Subandrio's diplomatic confrontation with the Dutch.[10] Operation Trikora was to unfold in three phases: infiltration, exploitation and consolidation, all under cover of the Indonesian Air Force. The plan called first for the insertion of small bands of Indonesian troops by sea and by airdrop, who would then draw Dutch forces away from areas where the exploitation phase would stage full-scale amphibious landings and paratroop operations to seize key locations. The consolidation phase would then expand Indonesian control over the whole of Western New Guinea.[4]

On 15 January 1962, the infiltration phase of Operation Trikora began when four Indonesian Navy motor torpedo boats attempted to land a unit of 150 marines on the south coast of New Guinea near Vlakke Hoek. The force was detected by a Dutch Lockheed P2V-7B Neptune aircraft and the Indonesian boats were intercepted by three Dutch destroyers. During the subsequent Battle of Arafura Sea, one Indonesian boat was sunk and two others were badly damaged and forced to retreat. Thus, this planned Indonesian amphibious landing ended disastrously with many crew members and marines being killed, among them Commodore Yos Sudarso, the Deputy Chief of the Indonesian Navy Staff. Some 55 survivors were captured. Over the next eight months, the Indonesian forces managed to insert 562 troops by sea and 1,154 by air drops. The inserted Indonesian troops conducted guerrilla operations throughout Western New Guinea from April 1962 onwards, but they were largely militarily ineffective. At least 94 Indonesian soldiers were killed and 73 were wounded during the hostilities. By contrast, the Dutch suffered only minimal casualties.[4][5]

Indonesian military activity continued to increase in the area through mid-1962 in preparation for the second phase of the operation. The Indonesian Air Force began to fly missions in the area from bases on surrounding islands, with Soviet-supplied Tupolev Tu-16 bombers armed with KS-1 Komet anti-ship missiles deployed in anticipation of an attack against the HNLMS Karel Doorman.[4][5]

By the summer of 1962, the Indonesian military had begun planning a large-scale amphibious and air assault against Biak, the Netherlands' main power base in West Irian. This operation would have been known as Operation Jayawijaya ("Victory over Imperialism") and would have included a substantial task force of 60 ships including several which had been supplied by Sukarno's Soviet and Eastern Bloc allies.[5][7] On 13 and 14 August 1962, air drops of Indonesian troops were staged from Sorong in the northwest to Merauke in the southeast as a diversion for an amphibious assault against the Dutch military base at Biak Island by a force of 7,000 Army (RPKAD) and Air Force (PASGAT) paratroopers, 4,500 marines and 13,000 army servicemen, from various military districts (KODAMs). However, the Dutch Navy's Marid 6 Netherlands New Guinea (Marid 6 NNG) signals intelligence section and Neptune aircraft detected the invasion force and alerted their command.[4][5]

According to Wies Platje, the Royal Netherlands Navy was responsible for the defence of Western New Guinea. In 1962, the Dutch naval presence in New Guinea consisted of five anti-submarine destroyers, two frigates, three submarines, one survey vessel, one supply ship and two oil tankers. Dutch air power in Western New Guinea consisted of eleven Lockheed P2V-7B Neptune aircraft from the Royal Netherlands Navy[14] plus 24 Hawker Hunter jet fighters from the Royal Netherlands Air Force. In addition, Dutch ground forces consisted of several anti-aircraft artillery units, five Royal Netherlands Marine Corps companies and three Royal Netherlands Army infantry battalions. As part of the planned defence, the Dutch had considered using Marid 6 NNG to disrupt the Indonesian military's communication systems.[5]

The Sukarno-era "West Irian Liberation Statue" in Jakarta

On 15 August 1962, the Netherlands recognized Indonesia's resolve to take Western New Guinea. Since it was unwilling to be drawn into a protracted conflict on the other side of the world, the Dutch government signed the New York Agreement, which handed the colony to an interim United Nations administration. Consequently, Operation Jayawijaya was called off and Western New Guinea was officially annexed by Indonesia in 1963. The Dutch decision to hand over Western New Guinea to Indonesia had been influenced by its main ally, the United States. While the Netherlands was a member of the North Atlantic Treaty Organization (NATO) and thus an ally of the Americans, the Kennedy Administration was unwilling to antagonize Indonesia since it was trying to court President Sukarno away from the Soviet orbit.[5] The Indonesian military's incursions into West Irian, plus the substantial Soviet military assistance to the Indonesian military, had convinced the United States government to pressure the Dutch to seek a peaceful solution to the conflict.[15]

The New York Agreement was the result of negotiations that were spearheaded by the American diplomat Ellsworth Bunker. As a face-saving measure for the Dutch, Bunker arranged for a Dutch-Indonesian ceasefire which would be followed by the handover of Western New Guinea on 1 October to a temporary United Nations Temporary Executive Authority (UNTEA). On 1 May 1963, Indonesia formally annexed Western New Guinea. As part of the New York Agreement, it was stipulated that a popular plebiscite, called the Act of Free Choice, would be held in 1969 to determine whether the West Papuans would choose to remain in Indonesia or seek self-determination.[16] However, American efforts to win over Sukarno proved futile and Indonesia turned its attention to the former British colony of Malaysia, resulting in the Indonesian-Malaysian Confrontation. Ultimately, President Sukarno was overthrown during the Indonesian coup d'état in 1965 and was replaced by the pro-Western Suharto.[4][5] The American mining company Freeport-McMoRan began exploiting Western New Guinea's copper and gold deposits.[17]

Following the Act of Free Choice plebiscite in 1969, West Papua was formally integrated into the Republic of Indonesia. Instead of a referendum of the 816,000 Papuans, they were represented by 1,022 Papuan tribal representatives for the vote. While several international observers including journalists and diplomats criticized the referendum as being rigged, the United States and Australia supported Indonesia's efforts to secure acceptance in the United Nations for the pro-integration vote. In all, 84 member states voted in favor for the United Nations to accept the result, with 30 others abstaining.[18] Due to the Netherlands' efforts to promote a West Papuan national identity, a significant number of West Papuans refused to accept the territory's integration into Indonesia. These formed the separatist Organisasi Papua Merdeka (Free Papua Movement) and have waged an insurgency against the Indonesian authorities, which still continues to this day.[7][19]