In the midst of all the tributes to Teddy Kennedy, which reflect conventional wisdoms concerning a conventional liberal Democratic party politician from a very powerful political family, one very unconventional and genuinely heroic act has been overlooked in the U.S.--Teddy Kennedy's rule in opposing the Pakistani army's invasion of East Pakistan and mass rape and murder of people in the region (people of Bengali ethno-cultural background who had long been treated as second class citizens by the central Pakistani government.)
The politics are very complicated and I will only mention them in the broadest outline. India was partitioned in the late 1940s into two states largely through the machinations of the retreating British imperialists and the Indian Moslem League, against the wishes of Gandhi, Nehru, and the main leaders of the independence movement. The partition for the most part made Muslim majority regions part of Pakistan and Hindu majority regions part of India, even though this meant that Muslim Pakistan was largely divided into two separate territories in the West and the East, with major ethnocultural differences and a thousand miles of Indian territory between the two regions--a completely unworkable situation which bred irredentist conflicts over the Northwest province of Kashmir, forced relocation of tens of millions of people between what had formerly been one India, and conflicts between different ethnocultural groups in West and East Pakistan separated by a thousand miles of Indian territory.
India became a leader of the non-aligned nations, developed friendly relations with the Soviet Union and pursued a peace oriented foreign policy and socialist oriented domestic policy under Congress Party led governments of Nehru and his successors, including his daughter, Indira Gandhi. Pakistan defining itself as a state for Indian Muslims became something like a Latin American junta state, with political parties and elections tolerated only as long as they did not threaten the reactionary landlord class and the political power structure for by and of the Muslim League. When elections seemed to threaten the existing order, generals stepped in and established a dictatorship over and over again.
The end of the 1960s, the most recent military dictator, General Yaya Khan, with advice and support from Henry Kissinger and the U.S. government, permitted elections to be held. The idea was to find a way to co-opt the Awami League, a rival to the Muslim League, which had large support in East Pakistan among its Bengali people. But the Awami League won an enormous victory in the elections in East Pakistan, creating a political crisis which lead General Yaya Khan to "cancel" the elections, arrest the leaders of the Awami League, and send the Pakistani army into East Pakistan to "put down" resistance, which meant widespread mass killing (Bangladeshi sources put the deaths at three million) which caught world attention, especially reports of the rape of hundreds of thousands of Bengali women by the Pakistani forces (many Bengali officers and soldiers of the Pakistani army, had rebelled against the terror and struggled to join the resistance.
From March of 1971 when the mass killing began to December when India intervened, the Nixon administration used its influence to block Indian military intervention in order to protect its Pakistani military ally (Pakistan had joined every cold war military pact that the U.S. set up in the region and its army and intelligence services were and are as connected to the U.S. military and intelligence services as they were previously to the British Empiore. Indira Gandhi, the Indian Prime Minister played the major role in winning support for Indian intervention through the world. Her greatest achievement, the signing of a 20 year friendship pact with the Soviet Union, more than anything else convinced Nixon and Kissinger to "let India intervene." Kissinger allegedly told the Indians very cynically that if the won quickly the U.S. would do nothing, but if the war dragged on it would have to "help" its "Pakistani ally." The Indian army intervened, was welcomed as liberators, crushed the now hated Pakistani army and forced it to surrender, and East Pakistan became the present state of Bangladesh.
But of all Americans, Teddy Kennedy played a very important and honorable role in these events. At a time when most Americans were understandably focused in the Vietnam War, Kennedy became the voice in the U.S. Congress denouncing the atrocities. More importantly he traveled to West Bengal (Indian Bengal) and other regions of India to observe the plight of and speak to refugees from the fighting. He returned to issue powerful report on what the Nixon administration had been seeking to hide, stating "nothing is more clear or more easily documented than the systematic campaign of terror and its genocidal consequences launched by the Pakistani army on March 25th  ... Hardest hit have been members of the Hindu community who have been robbed of their lands and shops, systematically slaughtered, and in some places painted with yellow patches marked 'H' [which was of course understood as a copying of the Yellow Star Nazis forced Jews to wear in occupied regions before the implementation of genocide.]
Kennedy concluded that "America's support of Islamabad [the central Pakistani government] is nothing short of complicity in the human and political tragedy in East Bengal."
Rarely in the cold war era or any era had a major establishment politician issued such a critique of U.S. official policy. Here of course it was both completely justified and in context courageous. Since Nixon feared Teddy Kennedy most of all as a potential rival in 1972, it may have even contributed to the administration's retreat on the issue (although I believe the the international criticism and especially the Indian Soviet Friendship Treaty were more important). As I see it, this was Teddy Kennedy's greatest accomplishment on foreign policy questions and it is an accomplishment of which Americans should be proud, just as we all should be ashamed of the more than half century support of dictatorial and adventurist regimes in Pakistan, a nation that today is both a nuclear power and the center for many destructive regional conflicts, especially the war in Afghanistan