The "ideology of Pakistan" was an incoherent mishmash prior to 1947 (mostly it was whatever Jinnah felt would work to get him the best deal...he himself seems to have had no coherent vision of the state he was demanding...and he more or less lost control of the narrative as the Aligarh boys simplified it into "Islam in danger" for the purposes of the 1946 election). What now passes for official Pakistani ideology was mostly put together AFTER partition and did not reach full flower till General Zia's time. It's creators took one strand of the original mishmash (Pakistan as Muslim Zion) and fashioned it into a millenarian fantasy about a vanguard Muslim state. Reality was never too close to the fantasy and remains impossibly distant even now, but enough people (meaning about 0.1% of the population, but maybe 25% of the educated military elite) are now part-time believers. In between normal activities like arranging tuition for their sons in American universities and buying and selling plots of lands in housing societies, these part-time believers sometimes start to believe "it can actually happen". To that extent, it matters and it is dangerous. It is easy to overestimate it's role in everyday life and in the actions of millions of ordinary people, but unfortunately the army's dominance as the "sole functioning institution" (a state of affairs they did much to create, with help from a generous and generally clueless Uncle Sam) means their vision of the national myth has undue influence...and their vision is heavily colored by this ideology.
Does that make some sort of sense?
I need more time to make this a coherent argument, but I am always hopeful that responses will lead to clarity....