I would like to learn more about any Islamic precepts which mandate that Muslims organize their society as an Islamic state governed by the Sharia.  Are there such precepts and where are they (Quran/Hadith)?  Establishment and maintenance of such government has been a central theme in many Muslim societies for centuries.  What mandates that a group of Muslims organize an Islamic government?  Are Muslims still required to strive for such government and laws even when minority in the country of residence?