LyrArc Article Gist
The issues related to India's borders all hinge on Tibet says the Council on Foreign Relations. Sardar Patel and Nehru had differences of their own on whether the McMahon Line set by the British in a treaty with Tibet as an independent country was the border with Tibet or the border with China.  Between 1913 and 1950 Tibet was an independent country, with an Indian High commissioner in Lhasa between 1947 and 1950. After the Cold War set in and China and the Soviet Union fought to defend the rights of colonial peoples the U.S. and Britain did not recognize Tibet as a part of China. Nehru simply remained with the British status quo of the McMahon line as the Indian border with Tibet, without any clear acceptance  of the invasion of Tibet in 1950 by China, yet accepting the new status quo after the invasion, differing from Sardar Patel on the issue.

This is why no clear picture emerges from looking at the official positions of the two countries, and a better understanding can be gained by looking at the border issue from the Council of Foreign Relations in the U.S.  

Essentially the border issue is not beneficial for what it gives back to each of the two countries. China sees itself rejecting the period of its weakness during the Japanese invasion so that it reasserts its position to borders that stretch outside where Chinese people live. India sees itself rejecting the weakness during the British period and the early post British period during which India was occupied with the issues relating to partition of British India and the partition of Kashmir.

This is why the Council on Foreign Relations can provide a better understanding from and independent perspective. 

Both sides have little to gain. China by being at the Tibetan border puts itself in a position where it has little to gain being on the border with a large rapidly industrializing country with a population of over 1 billion.  At over 4000 metres or 20,000 feet the territory and landscape is not one that humans can adapt too in any way, except for a few military personnel doing their term of duty of 6-12 months from India or China. China is even further away from the border as it is a remote border from Beijing, Shanghai, Canton or Chengdu, thousands of kilometres when it is just 8 hours from Srinagar by highway to Leh, Ladakh, and the Nepalese border very close to the Bihar state in India. The very distance suggests remoteness, with customs traditions in the region very different from that in China, suggesting very little connection between Beijing near Mongolia and Tibet or Ladakh very close to India by road or rail. To get some idea how close the Tibet border is to India consider that Rasuwagadhi Fort border point between Nepal and Tibet is only 127 miles by road from Kathmandu. The distance by rail from the Indian border in Bihar to the Nepalese border is only 34 kilometres with a new upgraded rail connection. Being this close India is likely to upgrade infrastructure throughout the northeast region as it upgrades infrastructure, roads and bridges and rail throughout India at an accelerated pace for economic development.