Islam puts a great weight on interpretation because in terms of size our Holy Book is the smallest and thus the most concentrated. Therefore, simple face value of the verses should not be taken. The Quran was the fulfillment of Allah's covenant to humans of SENDING us guidance directly now He will not do that i.e. you will not get another Prophet. Now, we have been taught the principles and must apply them. For that we are on our own. So applying this in terms of politics means that we not only should but must evolve a system of our own in terms of administration. See, if you are going to search up the Quran for guidance about road construction or city planning you are insulting the book and yourself! We must use the philosophical premise behind what the Quran says: fairplay, social justice, community consensus, accountability and so on to our political system rather than just copy paste what it states. If that were to be so then Saudi Arabia calls the Quran its constitution yet I do not know of a single instance in the Quran where it states that I, as a Muslim, should call a man my king.