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The Islamisation of laws under Zia was basically to feed his own interests,to stabilize/legitimize his power and to co operate with Muslim countries so as to get funds for propagation of Islamization and administrate the country which proved to be injurious for the country as it plunged the country into an unprecedented civil and external war.
According to Islamization laws schools were replaced by madarssas and urdu medium was taught.the degree of madarssa made equivalent to the masters degree.He created base of deobandi madaris (SSP) to support him.In this era number of madaris jumped to from 135 to 900 with 30,000 students and later on madarssas boomed to 50,000 with funds aiding by muslims countries such as Iran and Saudi arabia to sunni and shias respectively.Universities and agencies were assigned to implement Islamic transformation of society.Regular observance of prayers was made compulsory in offices and educational institutions during working hours.With the occurence of Iran revolution made Zia and Arab monarches nervous about fallout impacts,however shities were empowererd.To encounter this Zia adopted policy of strengthening anti-shia sects which gave rise to sectarianism.Zakat and Usher ordinance were base on sunni deobandi laws it enraged shias and wide scale gulf prevailed.Hudood ordinance was internationally criticized as it inflicted womens sharply in cotext of zina ordinance.
Zia encouraged religous parties to preach narrow version of Islam on the basis of sects and politically he pampered and empowered MQM to weaken the rising power of PPP which heightened sindhi muhajir tussle and strenthened ethnincity.The lashkare jahngvi grouo evolved form SSP.The encouragement and nourishment of taliban in the name of Islamisation to pursue jihadi movement and their present day activities has made hurdles for Pakistan to maintain friendly relations with the neighbouring countries.
During late 1970s Zia experimented religio politics by Islamisation,however,it cound not generate positive impact due to an ill policy and exploiting religion to gain support for another tenure.
Zia's project of Islamisation has far reaching political,religous,etnic and constitutional repurcussions on the society.wrong interpretation of Islam and governments wrong policies has long term implications on Pakistan which had cost it dearly.Since that period inconsistency and instability prevailed in Pakistan.