Civilizations develop at different rates. Less than 100 years ago, woman could not vote in the USA. 150 years ago, there was slavery in the USA. Six hundred years ago, the spanish inquisition was killing Muslims.

There are parts of the world that live like humans did thousands of years ago, There are parts that live like some did hundreds of years ago. I personally believe that some parts of the world have just not advanced. What you have is the modern "civilized" world clashing with parts of the world that have not developed to our standards. These terrorists are religious fanatics in the same vein as the spanish inquisition, believe what I believe or die.

Religion is a man made creation. It reflects who man is. The same "christian" religion of the inquisition is the same christian religion of Mother Teresa. Obviously the religion can be molded by humans to do whatever their wishes are. So are all muslims terrorists, of course not. Just like all christians are not abortion doctor killers. But there are those men who will make the religion what they want to adhere to their human beliefs.