You can never compare Islam with other religion though all Muslim have to believ Prophets starting from Adam to Last Prophet Mohammed. Besides, Sunna is not added to Koran . If you can not understand or find answer in Koran you refer to Hadith or Sunna.
Islam never preaches Voilency and those take the line of are not suppose to be muslim. You know all the big forces are behind creating terrirests like Bin Laden etc.
So you cannot blame Islam for terreriesm.
You cannot seperate faith and state as you are not faithful to you and your God you cannot be faithful to state also.