ISLAMIC  STATES?

A short while ago, I watched a BBC documentary on Dubai. Dubai is the unbelievable height of opulence. As I was watching the movie, I was wondering if Dubai was an Islamic state. Will someone please enlighten me if Koran approves of such opulence? I have read that Aurengzeb, whatever his shortcomings were, lived a life of a poor man, as the tenets of Koran demanded. Omar Mullar, the leader of the Taliban which swore by the Koran, lived in a luxurious palace. How was he accepted as the leader of the Taliban?

How do Dubai and the oil-rich Arabic countries justify themselves as Islamic states?

I am ignorant. Please, someone enlighten me.