Too many people think Islam is a violent religion because of the actions of a few. But one could think the same of Christianity. Does the Ku Klux Klan or Torquemada represent Christianity?
The Ku Klux Klan terrorized "uppity niggers" for a long list of imagined crimes and terrorized whites from opposing the Ku Klux Klan. The Klan used the cross as its symbol and even corrupted it by burning crosses in the yards of those who opposed them. They purported to be defending Christianity, but it wasn't the religion of Jesus.
Al Qaeda and the Taliban terrorize all those who don't agree with them for a long list of imagined crimes. They have used the Koran as their symbol, but ignore all those parts that don't fit their rigid view.
The Grand Inquisitor Torquemada tortured many people on real or imagined threats to Catholicism. Jews, Muslims, and Protestants were tortured to get them to confess to not following the "true belief". Torquemada worked with the blessing of King Phillip of Spain; religious orthodoxy was a means to quell dissent with his policies.
The Iranian government tortures many on real or imagined threats to Islam or its national security. But isn't it behaving like King Phillip? Religious orthodoxy is a means to quell dissent with its policies.
There are far too many historical cases of "bad apples" of any major religion; it makes it very easy to argue that any religion is violent.
What doesn't make the news is the multitude of people of all religious faiths who follow the example of the Good Samaritan, offering help to those in need regardless of differences. On the one hand we have Afghans offering tea to American soldiers who broke down their doors; on the other hand we have Americans sending money to the United Nations High Commission for Refugees for Pakistani flood victims.