Opposition to the partition of India

Opposition to the partition of India was widespread in India in the 20th century and it continues to remain a talking point in South Asian politics. Those who opposed it often adhered to the doctrine of composite nationalism. The Hindu, Christian, Anglo-Indian, Parsi and Sikh communities were largely opposed to the partition of India (and its underlying two-nation theory), as were many Muslims (these were represented by the All India Azad Muslim Conference).
Pashtun politician and Indian independence activist Khan Abdul Ghaffar Khan of the Khudai Khidmatgar viewed the proposal to partition India as un-Islamic and contradicting a common history in which Muslims considered India as their homeland for over a millennium. Mahatma Gandhi opined that "Hindus and Muslims were sons of the same soil of India; they were brothers who therefore must strive to keep India free and united."
Muslims of the Deobandi school of thought "criticized the idea of Pakistan as being the conspiracy of the colonial government to prevent the emergence of a strong united India" and helped to organize the Azad Muslim Conference to condemn the partition of India. They also argued that the economic development of Muslims would be hurt if India was partitioned, seeing the idea of partition as one that was designed to keep Muslims backward. They also expected "Muslim-majority provinces in united India to be more effective than the rulers of independent Pakistan in helping the Muslim minorities living in Hindu-majority areas." Deobandis pointed to the Treaty of Hudaybiyyah, which was made between the Muslims and Qureysh of Mecca, that "promoted mutual interaction between the two communities thus allowing more opportunities for Muslims to preach their religion to Qureysh through peaceful "tabligh"." Deobandi scholar Sayyid Husain Ahmad Madani argued for a united India in his book "Muttahida Qaumiyat Aur Islam" (Composite Nationalism and Islam), promulgating the idea that different religions do not constitute different nationalities and that the proposition for a partition of India was not justifiable, religiously.
Khaksar Movement leader Allama Mashriqi opposed the partition of India because he felt that if Muslims and Hindus had largely lived peacefully together in India for centuries, they could also do so in a free and united India. Mashriqi saw the two-nation theory as a plot of the British to maintain control of the region more easily, if India was divided into two countries that were pitted against one another. He reasoned that a division of India along religious lines would breed fundamentalism and extremism on both sides of the border. Mashriqi thought that "Muslim majority areas were already under Muslim rule, so if any Muslims wanted to move to these areas, they were free to do so without having to divide the country." To him, separatist leaders "were power hungry and misleading Muslims in order to bolster their own power by serving the British agenda."
In the 1946 Indian provincial elections, only 16% of Indian Muslims, mainly those from upper class, were able to vote. The common Indian Muslims, however, opposed the partition of India, believing that "that a Muslim state would benefit only upper-class Muslims."
The All India Conference of Indian Christians, representing the Christians of colonial India, along with Sikh political parties such as the Chief Khalsa Diwan and Shiromani Akali Dal led by Master Tara Singh condemned the call by separatists to create Pakistan, viewing it as a movement that would possibly persecute them.
Pakistan was created through the partition of India on the basis of religious segregation; the very concept of dividing the country of India along religious lines has been criticized as being a backward idea for the modern era. After it occurred, critics of the partition of India point to the displacement of fifteen million people, the murder of more than one million people, and the rape of 75,000 women to demonstrate the view that it was a mistake.
Indian Reunification proposals.
The subject of undoing the partition and reunifying India has been discussed by both Indians and Pakistanis. In "The Nation", Kashmiri Indian politician Markandey Katju has advocated the reunification of India with Pakistan under a secular government. He stated that the cause of the partition was the divide and rule policy of Britain, which was implemented to spread communal hatred after Britain saw that Hindus and Muslims worked together to agitate against their colonial rule in India. Katju serves as the chairman of the Indian Reunification Association (IRA), which seeks to campaign for this cause.
Pakistani historian Nasim Yousaf, the grandson of Allama Mashriqi, has also championed Indian Reunification and presented the idea at the New York Conference on Asian Studies on 9 October 2009 at Cornell University; Yousaf stated that the partition of India itself was a result of the British interests and their divide and rule policy that sought to create another buffer state between the Soviet Union and India to prevent the spread of Communism, as well the fact that a "division of the people and territory would prevent a united India from emerging as a world power and keep the two nations dependent on pivotal powers." Yousaf cited former Indian National Congress president Maulana Abul Kalam Azad, who wrote in the same vein:
Yousaf holds that "Muhammad Ali Jinnah, the President of the All-India Muslim League and later founder of Pakistan, had been misleading the Muslim community in order to go down in history as the saviour of the Muslim cause and to become founder and first Governor General of Pakistan." Allama Mashriqi, a nationalist Muslim, thus saw Jinnah as "becoming a tool in British hands for his political career." Besides the pro-separatist Muslim League, Islamic leadership in British India rejected the notion of partitioning the country, exemplified by the fact that most Muslims in the heartland of the subcontinent remained where they were, rather than migrating to newly created state of Pakistan. India and Pakistan are currently allocating a significant amount of their budget into military spending—money that could be spent in economic and social development. Poverty, homelessness, illiteracy, terrorism and a lack of medical facilities, in Yousaf's eyes, would not be plaguing an undivided India as it would be more advantaged "economically, politically, and socially." Yousaf has stated that Indians and Pakistanis speak a common lingua franca, Hindustani, "wear the same dress, eat the same food, enjoy the same music and movies, and communicate in the same style and on a similar wavelength". He argues that uniting would be a challenge, though not impossible, citing the fall of the Berlin Wall and the consequent German Reunification as an example.
French journalist François Gautier and Pakistani politician Lal Khan have expressed the view that Indian reunification would solve the conflict in the region of Jammu & Kashmir.