Wrong... India was not a united country prior to 1947. it had multiple states and territories. some of the states were in direct control of british and some were protectorates. some states didnt want to join indian union so they seperated themself to form Pakistan federation. contemporary india was never partition but u cant rule out the partition in future.
and regarding muslim backwardness well that fact of urs is also incorrect. u can see abdul kalam the nucleur scuientist, Areeb ahmed who workd to make ur chandrayaan a succeful story, yusuf hamid a billionaire, khans of bollywood and many more have immensely contributed their share of hardwork to make india a better place but sadly the majority indians r still backward due to its caste system.