Muslims who chose to migrate to Pakistan saw partition as an event of great self determination.
Hindus saw it as a reward to the Muslim league for their support in diluting the demand of Independence of India amongst Muslims who were fearful of reprisals in a Hindu dominated India.
British saw it as an opportunity to ensure that they will leave a telling memorial on the geo-politics of the sub-continent for years to come.
Any which of them could be right or equally wrong. Depends on which side of the Radcliffe line we stand.
If the 2 nation theory tries to establish that there were a mass of minority who did not identify with a united India in the events moving up to our Independence, I agree with that.
However, any proposition that the creation of Pakistan was based on any ideology but for Islamic, is blatantly false, specially when the basis of the two nation theory is religion itself.
It is also completely false that the idea of separate Independent muslim states was not envisaged or agreed to by Jinnah up till 1947. Following clause from the Muslim league resolution from March of 1940 makes that fact very clear:
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It can be agreed that Jinnah had not envisaged Pakistan to progress in to the current state of theological entity as it is now but that does not take away from the fact that the need for creation of Pakistan was justified on religious grounds in the Muslim League session of as early as 1930 with the original scheme put forward by Sir Mohamed Iqbal.
But that is now water under the bridge and we are where we are, Pakistan of today and India of today.
However, if analysing the argument that diversity could not have existed in a united India, we can take up the analysis of what was left of the population mix of India.
There have been blots on the way on the religious tolerance in India but all in all, with every event, religion has been taking a further back seat in the diverse, multi-religious, multi-cultural, multi-ethnic, multi-lingual, multi-colored Indian psyche over the last 60something years of our Independence. So may be not totally successful but it worked and India is at least as it was when we started the journey, if not better.
On the other hand if we look at the Islamic state of Pakistan founded on the premise that only a population of a uniform religious belief can exist together, we can compare the success of the idea and the efficacy of this 2 nation theory.
Pakistan lost half of its original composition in 1971. Though there was uniformity of religious belief in the two popuations, the diversity of ethinicity and color were so strong that it was progressively unsustainable for Bangladesh and Pakistan to exist together and so we then had 3 nations.
Further, the religion being the fundamental in creation of Pakistan, it is hardly surprising that turned in to an increasing influence in the national outlook of Pakistan. It became progressively necessary that the leaders, the intellectuals and even the defence forces drew their legitimacy and influence from the theological undercurrent of the nation.
It can be anybody's guess if things would have turned out in Pakistan like they have if it's creation was a natural coalscence of individuals, communities and religions over the years of history, wherein each religion and community would have had a say in the forging of the national outlook and opinion - something of the nature of what we call secularism in India.
So, we will only be clutching at straws trying to comparing the ascendancy charts of our two nations but then a good idea can be gauged from where we have both arrived.
Afterall like they say,
The proof of the pudding is in its eating.