ok, to original poster and all subsequent repliers, what does two nation theory mean today? there are already two nations now, theoretical level pe nahin practical level pe. maybe we should introduce a new term two nation practice.
hindus and muslims are separate nations? in india of curse they are not. in india muslims and hindus live in sometimes tenuous but relative peace. inspite of periodic disturbances, no muslim from india is in any hurry to get up and leave for either bangladesh or pakistan. no muslim groups with any significant support are demanding breakup of india on the basis of TNT. in any american university, in the indian community of students you find hindu and muslim students of india together. i have never seen a muslim student from india coming to study in US and living with pakistani roommates. it certainly may happen, but i have not seen them choose to do so. (i have seen hindu indian and pak muslim roommates)
muslim cricketers in indian team play very hard aganst pakistan. many musicians and artists from pak have moved to india, starting with the great star of classical music Bade ghulam ali khan sahab to adnan sami. there is no muslim group or party which advocates seperation of india or supports pak. even the SIMI and indian mujahideen accused of terrorism claim to do so becaue they think the indian state victmizes muslims (which it does every now and then) but do not advocate seperation of india.
is two nation theory valid in pakistan? depends on how the majority sunni muslims treat minority groups like sikhs hindus christians, ahmedis and even shias. i have no idea or no basis for making judgments. if you treat them well good, if not do better.