The process of national integration in Pakistan has been hampered by the interaction of two opposing forces: religion and ethnicity. While the Indian Muslims succeeded in establishing a state on the basis of the “Two Nation Theory" which argued that Muslims and Hindus were two separate and distinct ‘nations', Islam soon proved not to be the unifying force the national leaders had expected it to be. This was mainly due to the presence of three irreconciliable schools of thought, that is, the Modernists, the Traditionalists and the Fundamentalists, regarding the role Islam should have in the social and political order of the country. The persistent disagreement between the adherents of these three approaches has diminished the power of Islam as the most important locus for affective identity and, accordingly, strengthened the affective loyalty for ethnic groups.
Although Pakistan is certainly not unique in having a multi-ethnic character, it has been the consistent policy of the successive national governments to implement highly centralized systems of government which has compounded the centrifugal pull of ethnicity. The dissatisfaction with this policy has been reinforced by two elements: first, the centre's domination of the political system at the expense of the provinces is in direct contradiction with the 1940 Lahore Resolution which had guaranteed full provincial autonomy in the future state of Pakistan; and, second, the Punjabis' control of all major national institutions, including the armed forces and the civilian bureaucracy, has resulted in the 'peripheral' ethnic groups viewing centralization as being tantamount to the 'Punjabization' of Pakistani society.
Not only has the clash of religion and ethnicity created political instability and adversely affected the process of national integration, but the presence o f a hostile environment has further compounded the country's political developments. Surrounded by bellicose neighbours, and faced with the unenviable task of defending a territory which, until 1971, consisted of two wings separated from one another by over 1000 kilometres of Indian territory, the national leaders decided that the dual objectives of promoting a feeling of nationhood amongst the ethnic groups of the two wings and defending the country's national integrity would best be met by pursuing a strategy of centralization. It is this decision which led to increased Bengali demands for provincial autonomy, ultimately leading to the seccession of East Pakistan. And, although post-1971 Pakistan is certainly more easily defendable, this has not resulted in the central governments changing their approach.
In sum, it is the convergence of the three forces of religion, ethnicity and the external environment which has impeded the process of national integration in Pakistan. Until the national leaders are able to resolve the religious debate, reduce the centrifugal pull of ethnicity by granting provincial autonomy, the Pakistan polity will remain vulnerable to the influence of the external environment, and the process of national integration will continue to stagnate.