metis
aged ecumenical anthropologist
To be fair, insisting on the partition of India was not so much a problem as an indication of the problem.
Actually it was both, unless you're looking at this in a different way than I. Gandhi felt that Hindu and Muslem and others should live side-by-side in tolerance and peace, but Jinna refused that approach essentially stating that he and his fellow Muslems would not accept this. Nehru reluctantly agreed in order to try and prevent civil war, but bloodshed ended up being massive anyway even with the partitioning.