Why muslims are so violent?

just wondering why out of all the religions,islam seems to be the most angery,non god beliving religion,why are they mad that israel is rebuilding a ramp near a religious holy site,the muslims started violence,again.....they tell how its a good race,yet seem to spread violence,or get realy upset when ever someone has a bad opinion of them.and why is it ok the kill all other religions but thiers,just wondering,they seem to belive more in a warlord than god.it is well doented that mohammed was a ruthless killer,and alot of islam was taken from the jews....oddd,anyone know why