This is what happens when you chop a nation in half.

Before December 3, 1971, Pakistan was a country suffering from a split personality disorder. When British India became independent in 1947, the country was divided into Hindu India and Muslim Pakistan. The problem was that East Pakistan and West Pakistan were almost a thousand miles apart, and wedged in between them was archenemy India. Imagine if the United States only consisted of the East Coast and West Coast, and Russia controlled all of North America in between.

Thirteen days later, Pakistan had been amputated. Indian troops had conquered East Pakistan, which became the new nation of Bangladesh. More than ninety thousand Pakistani soldiers were taken prisoner, half the Pakistani Navy had been sunk and the Indian Air Force came out on top. It was total humiliation, and not just for Pakistan. The United States and Britain sent aircraft carriers in a futile attempt to intimidate India, and ended up facing off against Soviet warships. Pakistan’s defeat also spurred its rulers to begin development of nuclear weapons.

The 1971 India-Pakistan War, the third major conflict between the two nations in twenty-five years, was sparked by unrest in East Pakistan. The Bengalis of East Pakistan, who constituted 54 percent of Pakistan’s population at the time, chafed under the rule of West Pakistan. The two Pakistans belonged to different ethnic groups and spoke different languages.

Bengali demands for autonomy were rebuffed. By mid-1971, an East Pakistan guerrilla movement had emerged, supported by India. Pakistan’s military-controlled government cracked down hard, killing up to three million Bengalis in what has been described as a genocide. By November, both India and Pakistan were preparing for war.

On December 3, Pakistan launched a preemptive air strike against Indian airfields, ironically trying to emulate how the Israeli Air Force had destroyed Egyptian airpower in 1967. The difference was that the Israelis committed two hundred aircraft and wiped out nearly five hundred Egyptian aircraft in a few hours; Pakistan committed fifty aircraft and inflicted little damage. The air war featured the full panoply of Cold War jets, pitting Pakistani F-104 Starfighters, F-86 Sabres, MiG-19s and B-57 Canberras against Indian MiG-21s, Sukhoi-7s, Hawker Hunters and Folland Gnats, as well as Hawker Sea Hawks flying from the Indian carrier Vikrant.

Both sides claimed victory in the air war. Chuck Yeager, who was in Pakistan advising their air force, claimed the Pakistanis “whipped their asses.” The Indians claim Yeager was crazy. However, it does appear that India had the upper hand in the air, controlling the skies over East Pakistan and losing about forty-five aircraft to Pakistan’s seventy-five. The maneuverable little Indian Gnat, a British-made lightweight fighter (its predecessor was called the Midge), proved so successful against Pakistani F-86s that the Indians dubbed it the “Sabre Slayer.”

At sea, there is no question that India won. The Indian Navy dispatched missile boats, armed with Soviet-made Styx missiles, to strike the western port of Karachi, sinking or badly damaging two Pakistani destroyers and three merchant ships, as well as fuel tanks. Indian ships blockaded East Pakistan from reinforcements and supplies. Notable was India’s use of the carrier Vikrant to conduct air strikes on coastal targets, as well as conducting an amphibious landing on Pakistani territory.

Pakistan retaliated by dispatching the submarine Ghazi to mine Indian ports. While stalked by an Indian destroyer, the Ghazi mysteriously blew up. However, the submarine Hangor did sink the Indian frigate Khukri.

As for the ground war, the best that can be said is that if Napoleon himself had faced Pakistan’s strategic dilemma, he would have sulked off to St. Helena. Isolated by land and blockaded by sea, no army could have defended East Pakistan against even a moderately competent foe, let alone the nine Indian divisions that quickly captured the East Pakistan capital of Dhaka. East Pakistani forces surrendered on December 16.

To add insult to the defeat of Pakistan and its proudly Muslim rulers, the Indian campaign was planned by Maj. Gen. J. F. R. Jacob—an Indian Jew descended from a family that fled Baghdad in the eighteenth century.

One issue that hampered Pakistan’s war effort would soon become familiar in Iraq, Syria, Afghanistan and other ethnically divided nations. In 1971, Bengalis comprised a significant part of the Pakistani military, especially in technical jobs.

Meanwhile, the superpowers were flexing their muscles. Despite its cruelty toward the Bengalis, and the opposition of U.S. diplomats, President Richard Nixon and National Security Adviser Henry Kissinger backed Pakistan against pro-Soviet India (see the Nixon-Kissinger transcripts here). Task Force 74, centered on the aircraft carrier Enterprise, steamed into the Bay of Bengal, as did the British carrier Eagle. Why India would have been intimidated into a cease-fire, even as its tanks were rolling into Dhaka, is a mystery. America’s attempt to deter India from defeating Pakistan became a case study of the limitations of relying on the threat of force to compel other nations to change their behavior.

In fact, what the U.S. Navy accomplished was to chill U.S.-Indian relations for years. Even more disturbing were the Soviet cruisers, destroyers and submarines shadowing Task Force 74. A war between two Southwest Asian nations could have triggered a superpower showdown at sea, and perhaps World War III.

In the end, India had demonstrated its military superiority. Pakistan lost half its territory and population. Perhaps more important, Pakistani illusions that an Islamic army could rout the “weak” Hindus had been disproved. Following the 1947 and 1965 wars, the 1971 war was the third major conflict between India and Pakistan. It was also the last. Despite some hostilities in Kargil and other spots on the border, India and Pakistan have not fought a major war in forty-five years.

Unfortunately, Pakistan’s humiliation in 1971 spurred it into developing an atomic bomb. With India also armed with atomic weapons, South Asia now lives under the shadow of nuclear war. The next major India-Pakistan clash could be the last.

Michael Peck is a frequent contributor to the National Interest and is a regular writer for many outlets like WarIsBoring. He can be found on Twitter and Facebook.

Image: INS Vikramaditya in the Baltic Sea during trials in 2013. Wikimedia Commons/Indian Navy