I believe that this old post is a good summary as to why we see so much Muslim anger.
Muslims worldwide are angry over the "Jesus scopes". The scopes of some US sharpshooter’s weapons have numerical codes that refer to passages in the Bible. Naturally, nobody likes being shot at. But to do so with weapons with competing religious codes is particularly insulting to Muslims. In the past, I have noticed how Muslims are sensitive to insult.
Have you ever noticed how sensitive you become when you are angry? I am referring to sensitivity to others behavior, like cutting you off when you are driving or something that someone says that normally would not bother you that much. This is basic human nature at work. Anger in the Muslim world is a natural by-product of the Islamic system of governance and beliefs.
"Allah did not create man so that he could have fun. The aim of creation was for mankind to be put to the test through hardship and prayer. An Islamic regime must be serious in every field. There are no jokes in Islam. There is no humor in Islam. There is no fun in Islam. There can be no fun and joy in whatever is serious." -- Ayatollah Khomeini
This guy is an Islamic scholar. He may be a bit over the edge, but as he states, the basic ideology of Islam is very repressive.
Islam’s legal system is one of the most (If not THE most) harsh, brutal and repressive legal systems in the world. History has demonstrated time and again that repression of human nature tends to generate anger and violence. Humans (Like children) need a certain amount of restriction of behavior. We all need to have limits, otherwise chaos would result as everyone just did what they wanted to, including murder and other destructive behaviors. Like so many things in human experience, too many restrictions or too many limitations cause humans to resist or seek alternative behavior. I am not a psychologist, however my studies of warfare have shown that anger is an important part of courage. Anger can also cause you to make poor decisions in the ‘heat of the moment’. With undisciplined anger, violence is a natural byproduct. In the military, discipline is the vital training that soldiers need to learn how to handle the stress so that they can make cool decisions in the ‘heat of the moment’. Islam leaves out this vital training.
Humans will seek alternative avenues for emotions when under stress. Anger is a common emotional outlet in the Islamic world as it is one of the few emotions that is allowed to be expressed openly. As I have stated, I am not a psychologist, but it appears to me that the source of the anger management problems within the Islamic world is Islam itself. Just look at the symptoms. (Anger, hostility, sensitivity to insult, undisciplined violence)
I see so many descriptions (And film) of anger in the Muslim world when anything negative occurs concerning their ‘religion’. This anger is matched with open hostility. This hostility is directed against anyone for any supposed action that should not have been taken because we (whoever) lack sensitivity to Islam. In fact, sensitivity to insult is just about impossible to predict because so many different cases appear to exist that will in fact insult Muslims. And the human part about all of this is that I would act the same way, given the same repression.
The limitations that Muslims must live under (Both men and women) are enough to drive anyone to anger. You can’t even look at a pretty woman (Assuming that you can even see her) without having to avert your eyes. Many of the little enjoyments in life are taken away with few outlets for emotions that ALL humans have. Individuals can cope to varying degrees, but the overall result can only be anger, sensitivity to insult and violence. (Both organized and spontaneous)