Yeah well it also screwed China's image internationally.
The Chinese military action
has been viewed by the United States as part of the PRC's policy of making use of aggressive wars to settle its border disputes and to distract from its internal issues. According to James Calvin from the United States Marine Corps, western nations at the time viewed China as an aggressor during the China-India border war, and the war was part of a monolithic communist objective for a world dictatorship of the proletariat. This was further triggered by Mao Zedong's views that: "The way to world conquest lies through Havana, Accra, and Calcutta". Calvin believes that Chinese actions show a "pattern of conservative aims and limited objectives, rather than expansionism" and blames this particular conflict on India's provocations towards China. However, Calvin also expresses that China, in the past, has been adamant to gain control over regions to which it has a "traditional claim", which triggered the dispute over NEFA and Aksai Chin and indeed Tibet. Calvin's assumption, based on the history of the Cold War and the Domino Effect, assumed that China might ultimately try to regain control of everything that it considers as "traditionally Chinese" which in its view includes the entirety of South East Asia.
The Kennedy administration was disturbed by what they considered "blatant Chinese communist aggression against India". In a May 1963 National Security Council meeting, contingency planning on the part of the United States in the event of another Chinese attack on India was discussed. Defense Secretary Robert McNamara and General Maxwell Taylor advised the president to use nuclear weapons should the Americans intervene in such a situation. Kennedy insisted that Washington defend India as it would any ally, saying, "We should defend India, and therefore we will defend India". The Johnson Administration considered and then rejected giving nuclear weapons technology to the Indians.
The non-aligned nations, perhaps unsurprisingly, remained non-aligned, and only the United Arab Republic openly supported India. Of the non-aligned nations, six, Egypt, Burma, Cambodia, Sri Lanka, Ghana and Indonesia, met in Colombo on 10 December 1962. The proposals stipulated a Chinese withdrawal of 20 km from the customary lines without any reciprocal withdrawal on India's behalf. The failure of these six nations to unequivocally condemn China deeply disappointed India.
In 1972, Chinese Premier Zhou explained the Chinese point of view to President Nixon of the US. As for the causes of the war, Zhou asserted that China did not try to expel Indian troops from south of the McMahon line and that three open warning telegrams were sent to Nehru before the war. However, Indian patrols south of the McMahon line were expelled and suffered casualties in the Chinese attack. Zhou also told Nixon that Chairman Mao ordered the troops to return to show good faith.
The Indian government maintains that the Chinese military could not advance further south due to logistical problems and the cut-off of resource supplies.
While Western nations did not view Chinese actions favourably because of fear of the Chinese and competitiveness, Pakistan, which had had a turbulent relationship with India ever since the Indian partition, improved its relations with China after the war. Prior to the war, Pakistan also shared a disputed boundary with China, and had proposed to India that the two countries adopt a common defence against "northern" enemies (i.e. China), which was rejected by India. However, China and Pakistan took steps to peacefully negotiate their shared boundaries, beginning on 13 October 1962, and concluding in December of that year. Pakistan also expressed fear that the huge amounts of western military aid directed to India would allow it to threaten Pakistan's security in future conflicts. Mohammed Ali, External Affairs Minister of Pakistan, declared that massive Western aid to India in the Sino-Indian dispute would be considered an unfriendly act towards Pakistan. As a result Pakistan made efforts to improve its relations with China. The following year, China and Pakistan peacefully settled disputes on their shared border, and negotiated the China-Pakistan Border Treaty in 1963, as well as trade, commercial, and barter treaties. On 2 March 1963, Pakistan conceded its northern claim line in Pakistani-controlled Kashmir to China in favor of a more southerly boundary along the Karakoram Range. The border treaty largely set the border along the MacCartney-Macdonald Line. India's military failure against China would embolden Pakistan to initiate the Second Kashmir War with India. However, it effectively ended in a stalemate as Calvin states that the Sino-Indian War had caused the previously passive government to take a stand on actively modernising India's military. China offered diplomatic support to Pakistan in this war but did not offer military support. In January 1966, China condemned the Tashkent Agreement between India and Pakistan as a Soviet-US plot in the region. In the Indo-Pakistani War of 1971,
Pakistan expected China to provide military support, but it was left alone as India successfully helped the rebels in East Pakistan to found the new nation-state of Bangladesh.
And yes the rest
is history